Shared channel design around reserved resources

ABSTRACT

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may rate match an uplink transmission around a set of resources reserved by a base station. The base station may indicate a set of reserved resources which overlaps an uplink resource allocation to the UE. The base station may transmit an indicator of the reserved resources, and the UE may identify a location of a clear channel assessment (CCA) gap in a symbol period relative to the reserved resources. By rate matching around the reserved resources and one or more CCA gaps, the UE may transmit uplink information despite the allocated uplink resources colliding with the reserved resources.

CROSS REFERENCES

The present Application for Patent is a Continuation of U.S. patentapplication Ser. No. 16/406,624 by Bhattad et al., entitled “SHAREDCHANNEL DESIGN AROUND RESERVED RESOURCES” filed May 8, 2019, whichclaims the benefit of Indian Patent Application No. 201841017827 byBhattad et al., entitled “Shared Channel Design Around ReservedResources,” filed May 11, 2018, assigned to the assignee hereof, andexpressly incorporated herein.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to shared channel design around reserved resources.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform-spread-OFDM (DFT-S-OFDM). A wireless multiple-accesscommunications system may include a number of base stations or networkaccess nodes, each simultaneously supporting communication for multiplecommunication devices, which may be otherwise known as user equipment(UE).

A base station may provide a grant of uplink resources to a UE fortransmitting information via an uplink shared channel, such as aphysical uplink shared channel (PUSCH). In some examples, the UE and thebase station may communicate using a shared radio frequency spectrumband (e.g., an unlicensed radio frequency spectrum band). A wirelessdevice which wants to transmit on the shared radio frequency spectrumband may first perform a clear channel assessment (CCA) procedure beforetransmitting to determine whether any other wireless device is currentlytransmitting in the shared radio frequency spectrum band. If the sharedradio frequency spectrum band is available, the wireless device maytransmit after completing the CCA procedure. If unavailable, thewireless device may perform a subsequent CCA procedure at a later timebefore attempting to transmit on the shared radio frequency spectrumband. Conventional techniques for transmitting uplink transmission usinga shared radio frequency spectrum band are deficient.

SUMMARY

The techniques described herein generally relate to a user equipment(UE) rate matching an uplink transmission around a set of reservedresources and a clear channel assessment (CCA) gap. A base station mayindicate a set of reserved resources which may overlap with resources ofa shared radio frequency spectrum band in which the UE may be allocatedresources for transmitting an uplink transmission. In some cases, thebase station may explicitly indicate the locations of one or more CCAgaps. The reserved resources may include, for example, a physical randomaccess channel (PRACH) in which one or more wireless devices (e.g.,other UEs) may transmit a random access request when attempting toestablish connectivity with the base station. The CCA gap may bepositioned relative to the reserved resources to enable a wirelessdevice (e.g., second UE) to perform a CCA procedure within the CCA gap.If the CCA procedure indicates that the shared radio frequency spectrumband is available, the UE may send a transmission using the reservedresources. The UE may rate match its uplink transmission around thereserved resources and in the CCA gap to avoid transmitting in thereserved resources and in the CCA gap. Such rate matching may permit thereserved resources to remain accessible by other wireless devices. Byrate matching around the reserved resources and the CCA gap, the UE maytransmit uplink information despite the allocated uplink resourcescolliding with the reserved resources and the CCA gap.

A method of wireless communication at a UE is described. The method mayinclude receiving an indicator of reserved resources in a shared radiofrequency spectrum band, rating matching an uplink shared data channeltransmission around the reserved resources, and transmitting, within theshared radio frequency spectrum band, the rate matched uplink shareddata channel transmission.

An apparatus for wireless communication at a UE is described. Theapparatus may include a processor, memory in electronic communicationwith the processor, and instructions stored in the memory. Theinstructions may be executable by the processor to cause the apparatusto receive an indicator of reserved resources in a shared radiofrequency spectrum band, rate matching an uplink shared data channeltransmission around the reserved resources, and transmit, within theshared radio frequency spectrum band, the rate matched uplink shareddata channel transmission.

Another apparatus for wireless communication at a UE is described. Theapparatus may include means for receiving an indicator of reservedresources in a shared radio frequency spectrum band, rating matching anuplink shared data channel transmission around the reserved resources,and transmitting, within the shared radio frequency spectrum band, therate matched uplink shared data channel transmission.

A non-transitory computer-readable medium storing code for wirelesscommunication at a UE is described. The code may include instructionsexecutable by a processor to receive an indicator of reserved resourcesin a shared radio frequency spectrum band, rate matching an uplinkshared data channel transmission around the reserved resources, andtransmit, within the shared radio frequency spectrum band, the ratematched uplink shared data channel transmission.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a locationof a CCA gap relative to the reserved resources, and rate matching theuplink shared data channel transmission around the CCA gap.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the location ofthe CCA gap further may include operations, features, means, orinstructions for receiving a grant indicating allocated resources withinthe shared radio frequency spectrum band for the uplink shared datachannel transmission, the grant indicating that the CCA gap occurs at aparticular period of the allocated resources.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for performing a CCA priorto resuming transmission of the rate matched uplink shared data channeltransmission, in frequencies occupied by the reserved resources, afteran end of the reserved resources and a CCA gap.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the rate matched uplinkshared data channel transmission may be transmitted in an uplink shareddata channel and the indicator indicates a configuration of an uplinkchannel other than the uplink shared data channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the rate matched uplinkshared data channel transmission may be transmitted in an uplink shareddata channel and the indicator of the reserved resources includes animplicit indication of the reserved resources based on a configurationof a second uplink channel other than the uplink shared data channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the indicator ofthe reserved resources further may include operations, features, means,or instructions for receiving a broadcast signaling including theindicator of the reserved resources, where the indicator of the reservedresources may be specific to a cell that transmitted the broadcastsignaling.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the indicator ofthe reserved resources further may include operations, features, means,or instructions for receiving a control signaling including theindicator of the reserved resources, where the indicator of the reservedresources may be specific to the UE.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for selecting a collisionresponse from a set of different collisions responses based ondetermining that a reference signal may be scheduled for transmissionwithin the reserved resources.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for selecting the collisionresponse from the set of different collision responses based on a numberof symbols of the reference signal, a number of symbols of the referencesignal that collide with the reserved resources, a waveform type of theuplink shared data channel transmission, downlink control information(DCI) signaling, whether the reference signal may be scheduled fortransmission within the reserved resources, a type of the reservedresources, or any combination thereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the indicator may be a bitmapthat identifies a symbol level and resource block level rate matchingresource set.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the indicator may be a bitmapthat identifies a symbol level and sub-resource block level ratematching resource set.

A method of wireless communication at a UE is described. The method mayinclude receiving an indicator of a set of random access resources in ashared radio frequency spectrum band, identifying a location of a CCAgap between a first random access resource of the set of random accessresources and a second random access resource of the set of randomaccess resources, performing a CCA procedure during the CCA gap, anddetermining whether to transmit on the second random access resourcebased on a result of the CCA procedure.

An apparatus for wireless communication at a UE is described. Theapparatus may include a processor, memory in electronic communicationwith the processor, and instructions stored in the memory. Theinstructions may be executable by the processor to cause the apparatusto receive an indicator of a set of random access resources in a sharedradio frequency spectrum band, identify a location of a CCA gap betweena first random access resource of the set of random access resources anda second random access resource of the set of random access resources,perform a CCA procedure during the CCA gap, and determine whether totransmit on the second random access resource based on a result of theCCA procedure.

Another apparatus for wireless communication at a UE is described. Theapparatus may include means for receiving an indicator of a set ofrandom access resources in a shared radio frequency spectrum band,identifying a location of a CCA gap between a first random accessresource of the set of random access resources and a second randomaccess resource of the set of random access resources, performing a CCAprocedure during the CCA gap, and determining whether to transmit on thesecond random access resource based on a result of the CCA procedure.

A non-transitory computer-readable medium storing code for wirelesscommunication at a UE is described. The code may include instructionsexecutable by a processor to receive an indicator of a set of randomaccess resources in a shared radio frequency spectrum band, identify alocation of a CCA gap between a first random access resource of the setof random access resources and a second random access resource of theset of random access resources, perform a CCA procedure during the CCAgap, and determine whether to transmit on the second random accessresource based on a result of the CCA procedure.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the indicator indicates thatthe location of the CCA gap may be between the first random accessresource and the second random access resource.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the CCA gap includes aconfigurable number of symbol periods.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a random access occasionassociated with a random access resource of the set of random accessresources includes one or more of a random access cyclic prefixduration, a set of random access symbol periods, and a guard time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the location ofthe CCA gap further may include operations, features, means, orinstructions for determining that the CCA gap may be located between thefirst random access resource and the second random access resource.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, identifying the location ofthe CCA gap further may include operations, features, means, orinstructions for identifying the location of the CCA gap between eachpair of random access resources within the set of random accessresources.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that afirst subset of the set of random access resources correspond to a firsttransmission time interval (TTI) and a second subset of the set ofrandom access resources correspond to a second TTI, and determiningwhether to use the second subset of the set of random access resourcesto transmit a random access message.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining whether to usethe second subset of the set of random access resources further mayinclude operations, features, means, or instructions for determining touse the second subset of the set of random access resources to send therandom access message based on a TTI type indicator or a subframe formatindicator (SFI) associated with the second TTI.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining whether to usethe second subset of the set of random access resources further mayinclude operations, features, means, or instructions for receiving aconfiguration message that indicates whether to use a random accessresource of the set of random access resources that occurs within thesecond TTI.

A method of wireless communication at a base station is described. Themethod may include transmitting an indicator of reserved resources in ashared radio frequency spectrum band, receiving, within the shared radiofrequency spectrum band, a rate matched uplink shared data channeltransmission, and de-rating matching the rate matched uplink shared datachannel transmission based on the reserved resources.

An apparatus for wireless communication at a base station is described.The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to transmit an indicator of reserved resources in a sharedradio frequency spectrum band, receive, within the shared radiofrequency spectrum band, a rate matched uplink shared data channeltransmission, and de-rate matching the rate matched uplink shared datachannel transmission based on the reserved resources.

Another apparatus for wireless communication at a base station isdescribed. The apparatus may include means for transmitting an indicatorof reserved resources in a shared radio frequency spectrum band,receiving, within the shared radio frequency spectrum band, a ratematched uplink shared data channel transmission, and de-rating matchingthe rate matched uplink shared data channel transmission based on thereserved resources.

A non-transitory computer-readable medium storing code for wirelesscommunication at a base station is described. The code may includeinstructions executable by a processor to transmit an indicator ofreserved resources in a shared radio frequency spectrum band, receive,within the shared radio frequency spectrum band, a rate matched uplinkshared data channel transmission, and de-rate matching the rate matcheduplink shared data channel transmission based on the reserved resources.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a locationof a CCA gap relative to the reserved resources, and de-rate matchingthe rate matched uplink shared data channel transmission based on thelocation of the CCA gap.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting a grantindicating the location of the CCA gap.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the indicator may be a bitmapthat identifies a symbol level and resource block level rate matchingresource set or identifies a symbol level and sub-resource block levelrate matching resource set.

A method of wireless communication at a base station is described. Themethod may include transmitting an indicator of a set of random accessresources in a shared radio frequency spectrum band, identifying alocation of a CCA gap between a first random access resource of the setof random access resources and a second random access resource of theset of random access resources, and monitoring the second random accessresource based on the location of the CCA gap.

An apparatus for wireless communication at a base station is described.The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to transmit an indicator of a set of random access resourcesin a shared radio frequency spectrum band, identify a location of a CCAgap between a first random access resource of the set of random accessresources and a second random access resource of the set of randomaccess resources, and monitor the second random access resource based onthe location of the CCA gap.

Another apparatus for wireless communication at a base station isdescribed. The apparatus may include means for transmitting an indicatorof a set of random access resources in a shared radio frequency spectrumband, identifying a location of a CCA gap between a first random accessresource of the set of random access resources and a second randomaccess resource of the set of random access resources, and monitoringthe second random access resource based on the location of the CCA gap.

A non-transitory computer-readable medium storing code for wirelesscommunication at a base station is described. The code may includeinstructions executable by a processor to transmit an indicator of a setof random access resources in a shared radio frequency spectrum band,identify a location of a CCA gap between a first random access resourceof the set of random access resources and a second random accessresource of the set of random access resources, and monitor the secondrandom access resource based on the location of the CCA gap.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the indicator indicates thatthe location of the CCA gap may be between the first random accessresource of the set of random access resources and the second randomaccess resource of the set of random access resources.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the CCA gap includes aconfigurable number of symbol periods.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving a randomaccess message during the first random access resource of the set ofrandom access resources.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving a randomaccess message during each random access resource of the set of randomaccess resources.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports shared channel design around reserved resources inaccordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure.

FIG. 3 illustrates an example of a resource grid that supports sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure.

FIG. 4 illustrates an example of a resource grid that supports sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure.

FIG. 5 illustrates examples of collision response schemes that supportshared channel design around reserved resources in accordance withaspects of the present disclosure.

FIG. 6 illustrates an example of back to back RACH occasions thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure.

FIG. 7 illustrates an example of back to back RACH occasions thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure.

FIGS. 8 through 11 illustrate examples of multiple CCA sensing occasionschemes that supports shared channel design around reserved resources inaccordance with aspects of the present disclosure.

FIGS. 12 and 13 illustrate examples of process flows that support sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure.

FIGS. 14 and 15 show block diagrams of devices that support sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure.

FIG. 16 shows a block diagram of a communications manager that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure.

FIG. 17 shows a diagram of a system including a device that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure.

FIGS. 18 and 19 show block diagrams of devices that support sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure.

FIG. 20 shows a block diagram of a communications manager that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure.

FIG. 21 shows a diagram of a system including a device that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure.

FIGS. 22 through 28 show flowcharts illustrating methods that supportshared channel design around reserved resources in accordance withaspects of the present disclosure.

DETAILED DESCRIPTION

The techniques described herein generally relate to a user equipment(UE) transmitting an uplink transmission around a set of reservedresources and a clear channel assessment (CCA) gap. Transmitting anuplink transmission around a set of reserved resource and the CCA gapmay include rate matching, or puncturing, or a combination thereof. Ratematching and puncturing may be used interchangeably such that if ratematching is described, puncturing or another method may also apply. Abase station may transmit an indicator of reserved resources which, insome examples, may overlap with resources of a shared radio frequencyspectrum band in which the UE may be allocated resources fortransmitting an uplink transmission. The CCA gap may be positionedrelative to the reserved resources to enable a wireless device (e.g.,second UE) to perform a CCA procedure within the CCA gap. The UE mayrate match its uplink transmission around the reserved resources and theCCA gap to avoid transmitting in the reserved resources and in the CCAgap. By rate matching around the reserved resources, the UE may be ableto transmit uplink information despite the allocated uplink resourcescolliding with the reserved resources and the CCA gap. Thus, thetechniques described herein may efficiently use the shared radiofrequency spectrum band and use CCA gaps for maintaining fair access tothe reserved resources for a number of UEs.

Wireless devices communicating using the shared radio frequency spectrumband may perform a CCA prior to transmitting on the reserved resources.To accommodate use of the reserved resources, the UE may not transmit ina CCA gap that is located relative to the reserved resources. The UE mayrate match around the CCA gap and the reserved resources to allowwireless devices (e.g., other UEs or itself) to perform a CCA in the CCAgap and transmit using the reserved resources. In some cases, the UE maytransmit in symbol periods of the allocated resources after the reservedresources. In some cases, the reserved resources and CCA gap indicatorsmay be UE-specific or cell-specific. The reserved resources may, forexample, only span a few symbols in a slot. The reserved resources maybe a random access channel (RACH), a physical uplink control channel(PUCCH), or the like. In some examples, the UE may use the reservedresources for transmitting a sounding reference signal (SRS), uplinkultra-reliable low latency communications (URLLC), or for other uplinkcommunications.

In some cases, a grant indicating an uplink resource allocation to a UEmay also indicate the reserved resources. In some cases, the reservedresources may be indicated separately from the grant. The UE may ratematch around the reserved resources when transmitting uplinkinformation. In some cases, the reserved resources may occupy adiscontinuous set of frequencies. In some cases, if the reservedresources do not occupy the entire allocated bandwidth, the UE maytransmit using a subset of the allocated bandwidth which does notoverlap with the reserved resources. The UE may transmit on the subsetof the allocated bandwidth using a different power spectral density(PSD) than when transmitting on the full allocated bandwidth. In somecases, the UE may perform a CCA prior to resuming transmission of therate matched uplink shared data channel transmission, in frequenciesoccupied by the reserved resources, after an end of the reservedresources and the CCA gap.

The base station may transmit an indicator of the reserved resources toUE, and, in some examples, the UE may identify the reserved resourcesand any CCA gaps associated with the reserved resources based on theindicator. The reserved resources and the CCA gaps may be explicitly orimplicitly indicated by the base station, and indicators for differentrate matched resources may be transmitted by different layers or usingdifferent techniques (e.g., implicitly vs explicitly). In some cases,the indicators for different rate matched resources may be transmittedat different times. In some cases, the base station may not explicitlyindicate the reserved resources by an indicator. For example, the UE mayidentify a RACH configured by the base station and implicitly assumethis as a reserved resource. In some cases, the reserved resources maybe scheduled for the same time and frequency resources as a demodulationreference signal (DMRS). The UE may implement techniques to handlecollisions between a DMRS transmission and the reserved resources.

Aspects of the disclosure are initially described in the context of awireless communications system. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to uplink shared channeldesign around reserved resources and multiple CCA sensing locations foran uplink burst grant. Aspects of the disclosure are further illustratedby and described with reference to apparatus diagrams, system diagrams,and flowcharts that relate to shared channel design around reservedresources and CCA gaps.

FIG. 1 illustrates an example of a wireless communications system 100that supports shared channel design around reserved resources inaccordance with aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A)network, an LTE-A Pro network, or a New Radio (NR) network. In somecases, wireless communications system 100 may support enhanced broadbandcommunications, ultra-reliable (e.g., mission critical) communications,low latency communications, or communications with low-cost andlow-complexity devices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation Node B orgiga-nodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may be called forward linktransmissions while uplink transmissions may be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up only a portion of the geographic coverage area110, and each sector may be associated with a cell. For example, eachbase station 105 may provide communication coverage for a macro cell, asmall cell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples half-duplexcommunications may be performed at a reduced peak rate. Other powerconservation techniques for UEs 115 include entering a power saving“deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1 or otherinterface). Base stations 105 may communicate with one another overbackhaul links 134 (e.g., via an X2 or other interface) either directly(e.g., directly between base stations 105) or indirectly (e.g., via corenetwork 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 MHz to 300 GHz.Generally, the region from 300 MHz to 3 GHz is known as the ultra-highfrequency (UHF) region or decimeter band, since the wavelengths rangefrom approximately one decimeter to one meter in length. UHF waves maybe blocked or redirected by buildings and environmental features.However, the waves may penetrate structures sufficiently for a macrocell to provide service to UEs 115 located indoors. Transmission of UHFwaves may be associated with smaller antennas and shorter range (e.g.,less than 100 km) compared to transmission using the smaller frequenciesand longer waves of the high frequency (HF) or very high frequency (VHF)portion of the spectrum below 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that can tolerate interference from otherusers.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a CA configurationin conjunction with CCs operating in a licensed band (e.g., LAA).Operations in unlicensed spectrum may include downlink transmissions,uplink transmissions, peer-to-peer transmissions, or a combination ofthese. Duplexing in unlicensed spectrum may be based on frequencydivision duplexing (FDD), time division duplexing (TDD), or acombination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving devices are equipped with one ormore antennas. MIMO communications may employ multipath signalpropagation to increase the spectral efficiency by transmitting orreceiving multiple signals via different spatial layers, which may bereferred to as spatial multiplexing. The multiple signals may, forexample, be transmitted by the transmitting device via differentantennas or different combinations of antennas. Likewise, the multiplesignals may be received by the receiving device via different antennasor different combinations of antennas. Each of the multiple signals maybe referred to as a separate spatial stream and may carry bitsassociated with the same data stream (e.g., the same codeword) ordifferent data streams. Different spatial layers may be associated withdifferent antenna ports used for channel measurement and reporting. MIMOtechniques include single-user MIMO (SU-MIMO) where multiple spatiallayers are transmitted to the same receiving device, and multiple-userMIMO (MU-MIMO) where multiple spatial layers are transmitted to multipledevices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105. Some signals, such as datasignals associated with a particular receiving device, may betransmitted by a base station 105 in a single beam direction (e.g., adirection associated with the receiving device, such as a UE 115). Insome examples, the beam direction associated with transmissions along asingle beam direction may be determined based at least in in part on asignal that was transmitted in different beam directions. For example, aUE 115 may receive one or more of the signals transmitted by the basestation 105 in different directions, and the UE 115 may report to thebase station 105 an indication of the signal it received with a highestsignal quality, or an otherwise acceptable signal quality. Althoughthese techniques are described with reference to signals transmitted inone or more directions by a base station 105, a UE 115 may employsimilar techniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115), or transmitting a signal in asingle direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based at least inpart on listening according to different receive beam directions (e.g.,a beam direction determined to have a highest signal strength, highestsignal-to-noise ratio, or otherwise acceptable signal quality based atleast in part on listening according to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may insome cases perform packet segmentation and reassembly to communicateover logical channels. A Medium Access Control (MAC) layer may performpriority handling and multiplexing of logical channels into transportchannels. The MAC layer may also use hybrid automatic repeat request(HARQ) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and a base station 105 or corenetwork 130 supporting radio bearers for user plane data. At thePhysical (PHY) layer, transport channels may be mapped to physicalchannels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s=)1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a mini-slot or a symbol of a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an E-UTRA absolute radiofrequency channel number (EARFCN)) and may be positioned according to achannel raster for discovery by UEs 115. Carriers may be downlink oruplink (e.g., in an FDD mode), or be configured to carry downlink anduplink communications (e.g., in a TDD mode). In some examples, signalwaveforms transmitted over a carrier may be made up of multiplesub-carriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiplexing (OFDM) or DFT-s-OFDM).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR,etc.). For example, communications over a carrier may be organizedaccording to TTIs or slots, each of which may include user data as wellas control information or signaling to support decoding the user data. Acarrier may also include dedicated acquisition signaling (e.g.,synchronization signals or system information, etc.) and controlsignaling that coordinates operation for the carrier. In some examples(e.g., in a carrier aggregation configuration), a carrier may also haveacquisition signaling or control signaling that coordinates operationsfor other carriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a system bandwidth of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may consist ofone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 and/or UEs 115 that can support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communications system 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation (CA) or multi-carrier operation. A UE 115 may beconfigured with multiple downlink CCs and one or more uplink CCsaccording to a carrier aggregation configuration. Carrier aggregationmay be used with both FDD and TDD component carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including wider carrier or frequency channel bandwidth, shortersymbol duration, shorter TTI duration, or modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a suboptimal or non-ideal backhaullink). An eCC may also be configured for use in unlicensed spectrum orshared spectrum (e.g., where more than one operator is allowed to usethe spectrum). An eCC characterized by wide carrier bandwidth mayinclude one or more segments that may be utilized by UEs 115 that arenot capable of monitoring the whole carrier bandwidth or are otherwiseconfigured to use a limited carrier bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than otherCCs, which may include use of a reduced symbol duration as compared withsymbol durations of the other CCs. A shorter symbol duration may beassociated with increased spacing between adjacent subcarriers. Adevice, such as a UE 115 or base station 105, utilizing eCCs maytransmit wideband signals (e.g., according to frequency channel orcarrier bandwidths of 20, 40, 60, 80 MHz, etc.) at reduced symboldurations (e.g., 16.67 microseconds). A TTI in eCC may consist of one ormultiple symbol periods. In some cases, the TTI duration (that is, thenumber of symbol periods in a TTI) may be variable.

In some cases, base station 105 may use a block interlace structure forPRACH. A shared radio frequency spectrum band (e.g., an unlicensed band)may have regulatory limits on the total power transmitted and the PSD.The PSD limit in the shared radio frequency spectrum band is typicallydefined as maximum power in a 1 MHz bandwidth. For example, a PSD limitthat may be mandated is 10 dBm/MHz, meaning that the max powertransmitted in any 1 MHz bandwidth should be less than or equal to 10dBm. In a typical 20 MHz bandwidth communication the transmit power islimited by the PSD limit. In enhanced licensed assisted access (eLAA),interlaced allocation in the uplink may be used to overcome the PSDlimitation on the total power. If a UE is allocated dis-contiguouschunks of frequencies within the bandwidth, where each chunk isseparated from its neighbor by more than 1 MHz, then each chunk cantransmit the full 10 dBm for example. In eLAA, for a 20 MHz bandwidththere are a total of 100 resource blocks (RBs). The 100 RBs may bedivided into 10 interlaces of 10 RBs each, where RBs in each interlaceare spaced by 10 RBs. For example, if the RBs are numbered 0-99,interlace0 is defined as {0,10,20, . . . ,90}, the interlace1 is{1,11,21, . . . 91}, and so forth. Thus, in any given interlace, thereis 1 RB within any 1 MHz bandwidth, whereas the total allocation is 10RBs and the maximum power that can be transmitted is 23 dBm. If the 10RBs had be allocated contiguously, the UE 115 can transmit a max of 16dBm power due to 10 contiguous RBs covering 2 MHz bandwidth. In someexamples, a UE 115 may be allocated resources in the granularity ofinterlaces. The regulatory specification may also specify occupiedchannel bandwidth (OCB) (e.g., the OCB is to span 80% of the totalbandwidth). The interlace definitions ay help meet the OCB requirementsand, in some examples, it may be permitted to not meet this criteria foroccasional short transmissions.

Wireless communications systems such as an NR system may utilize anycombination of licensed, shared, and unlicensed spectrum bands, amongothers. The flexibility of eCC symbol duration and subcarrier spacingmay allow for the use of eCC across multiple spectrums. In someexamples, NR shared spectrum may increase spectrum utilization andspectral efficiency, specifically through dynamic vertical (e.g., acrossthe frequency domain) and horizontal (e.g., across the time domain)sharing of resources.

A UE 115 may rate match an uplink transmission around a set of resourcesreserved by a base station 105. The base station 105 may indicate thereserved resources which may overlap with an uplink resource allocationto the UE 115. The UE 115 may further identify a location of a CCA gapin a symbol period relative to the reserved resources. By rate matchingan uplink transmission around the reserved resources and the CCA gap,the UE 115 may be able to still transmit uplink information despite theallocated uplink resources colliding with the reserved resources.

FIG. 2 illustrates an example of a wireless communications system 200that supports shared channel design around reserved resources inaccordance with aspects of the present disclosure. In some examples,wireless communications system 200 may implement aspects of wirelesscommunications system 100.

Base station 105-a may serve UE 115-a and UE 115-b and communicate withthe UEs 115 using a shared radio frequency spectrum band (e.g., anunlicensed radio frequency spectrum band). Base station 105-a maytransmit a grant indicating an uplink resource allocation within theshared radio frequency spectrum band for the UE to transmit an uplinktransmission (e.g., a physical uplink shared channel (PUSCH)transmission). There may be a CCA gap reserved for a CCA procedurebetween random access resources. Prior to transmitting, the UE 115 mayperform a CCA procedure, such as an LBT procedure, to determine whetherthe shared radio frequency spectrum band is available (e.g., notcurrently being used by another detectable wireless device). If the UE115 determines that the shared radio frequency spectrum band isavailable, the UE 115 may transmit uplink information to base station105-a. For example, if UE 115-a is granted an uplink resource allocationon uplink connection 210-a, UE 115-a may perform a CCA procedure. If UE115-a determines that the shared radio frequency spectrum band passesthe CCA procedure, UE 115-a may transmit uplink data to base station105-a using the shared radio frequency spectrum band. The UE 115 maydetermine whether to transmit on the uplink transmission or randomaccess resources based on the CCA gap.

Base station 105-a may indicate a set of reserved resources in theshared radio frequency spectrum band, shown by the reserved resources215. For example, the indication may be transmitted on a downlinkconnection 205-a. The reserved resources 215 may be reserved forspecific UEs 115 (e.g., UE-specific) or on a per-cell basis (e.g.,cell-specific), where any served or attached UE 115 may use the reservedresources 215. In some cases, the reserved resources 215 may only span afew symbols in a TTI. The UE or UEs 115 may use the reserved resources215 for a RACH (e.g., a Physical RACH (PRACH)), transmitting a soundingreference signal (SRS), a physical uplink control channel (PUCCH), oruplink ultra-reliable low latency communications (URLLC), among otheruplink communications. In some cases, such as if the reserved resources215 are for PRACH transmissions, base station 105-a may use a knownPRACH sequence having increased sub-carrier spacing (SCS) or use a toneinterlace structure. In some cases, base station 105-a may use a blockinterlace structure for a reserved resource such as a PRACH.

In some cases, base station 105-a may transmit to the UE 115-a a grantthat indicates the reserved resources 215 and an uplink resourceallocation for UE 115-a. UE 115-a may rate match an uplink transmissionaround the reserved resources 215 when transmitting uplink information.For example, UE 115-a may transmit uplink information in up to allresource elements of a resource allocation indicated in a grant, otherthan resource elements of the reserved resources 215. In some cases, ifthe reserved resources 215 do not occupy the entire allocated bandwidth,UE 115-a may transmit at the same time as the reserved resources 215using a subset of the allocated bandwidth which do not overlap with thereserved resources 215 in the frequency domain. UE 115-a may transmit onthe subset of the allocated bandwidth using a different power spectraldensity (PSD) than when transmitting on the full allocated bandwidth(e.g., as explain in more detail in FIG. 4).

Wireless devices operating in the wireless communications system 200 mayperform a CCA procedure prior to transmitting on the reserved resources215. To enable performance of the CCA procedure, a CCA gap may bedefined relative to the reserved resources 215. The UE 115-a may alsorate match around the CCA gap and the reserved resources 215 to allowwireless devices (e.g., other UEs 115 or itself) to use the CCA gap toperform a CCA procedure and transmit using the reserved resources 215.In some cases, the CCA gap may be aligned with or adjacent to thereserved resources 215, such that a wireless device may perform a CCAduring the CCA gap, and then transmit using the reserved resources 215in the following symbol period. The UE 115-a may skip transmittingwithin the CCA gap, to avoid interfering with other wireless devicesperforming a CCA procedure within the CCA gap, thereby providing a fairopportunity for the other wireless devices to gain access to thetransmission medium for transmitting using the reserved resources.

UE 115-a may transmit an uplink transmission around a set of reservedresources and a CCA gap. Transmitting an uplink transmission around aset of reserved resources and the CCA gap may include rate matching, orpuncturing, or a combination thereof. Rate matching and puncturing maybe used interchangeably such that if rate matching is described,puncturing or another method may also apply. In some cases, UE 115-a mayattempt to continue transmitting its rate matched uplink transmission insymbol periods of the allocated resources after the reserved resources215. To do so, UE 115-a may perform a CCA after the reserved resourcesand/or the CCA gap to confirm that the shared radio frequency band isavailable. If UE 115-a does not transmit in parallel with the reservedresources but transmits after the reserved resources, an additional CCAgap may be provided after the reserved resources for UE 115-a to performthe CCA. In some cases, UE 115-a may transmit around the reservedresources, CCA gaps before the reserved resources and potential CCA gapafter the reserved resources. UE 115-a may perform such transmissionsusing rate matching or puncturing its planned transmission around theCCA gaps and reserved resources.

In some examples, base station 105-a may transmit an indicator 220 ofthe reserved resources 215 to UE 115-a. UE 115-a may identify thereserved resources 215 based on the indicator 220 and rate match aroundthe reserved resources 215 and any CCA gaps associated with the reservedresources 215. The format of the indicator 220 or technique ofindicating the resources may be based on one or more of whether thereserved resources 215 are UE-specific or cell-specific, the location ofthe reserved resources 215 relative to the resources allocated for UE115-a, the use of the reserved resources 215 (e.g., PRACH, SRS, PUCCH,etc.), or the like.

In some cases, the indicator 220 may provide an explicit indication ofthe reserved resources (e.g., symbol period and tone), or the indicator220 may include other information, and UE 115-a may implicitly identifythe time and frequency information of the reserved resources 215, theCCA gap, or both, from the indicator 220. The indicator 220 may alsoinclude explicit or implicit indications of CCA gaps for the reservedresources 215. For example, the indicator 220 may explicitly indicateone of more symbol periods for a CCA gap, or UE 115-a may determine thesymbol periods for the CCA gap based on the time and frequency resourcesof the reserved resources 215.

As an example of an explicit indication, the indicator 220 may include abitmap which indicates the reserved resources at a symbol level in timeand an RB level or sub-RB level in frequency. For example, each value inthe bitmap may correspond to a resource in time and frequency at asymbol level and tone, resource block, or sub-resource block level. Insome examples, a same RB level bitmap, or sub-RB level bitmap, may applyto every symbol in a symbol level bitmap.

In some cases, the wireless communications system 200 may use symbol-RBlevel rate matching. UE 115-a may identify the time and frequencyinformation for the reserved resources 215 and rate match a transmission(e.g., PUSCH, PUCCH, etc.) around the reserved resources 215 at a symbollevel in time and an RB level or sub-RB level in frequency and aroundone or more CCA gaps. An example of sub-RB may include 2, 3, 4, or 6resource elements (REs), where rate matching at a sub-RB level is ratematching around REs. In some cases, UE 115-a may implement symbol-RBlevel rate matching for any format of indication or rate matchingdescribed herein.

As an example of an implicit indication, the indicator 220 may be a partof a grant transmitted by base station 105-a. Base station 105-a may notschedule UE 115-a for the allocated resources which overlap the reservedresources 215. UE 115-a may identify the reserved resources 215 based onthe scheduling. For example, if UE 115-a is not scheduled for PUSCHtransmission on certain tones during certain symbol periods, UE 115-amay implicitly determine those tones and symbol periods are used for thereserved resources 215, the CCA gap, or both. In some cases, basestation 105-a may configure the reserved resources 215 for a channelsuch as RACH, and UE 115-a may determine implicitly to rate match aroundthe reserved resources 215 when a grant allocates resources for atransmission (e.g., PUSCH) that collides with the reserved resources215.

Resources that the UE 115-a is to rate match around, such as CCA gaps,UE-specific reserved resources, or cell-specific reserved resources, maybe configured via different indications and at different layers orlevels. For example, if the reserved resources 215 are cell-specific,the indicator 220 of the reserved resources 215 may be broadcast insystem information (e.g., in a system information block (SIB)),indicated in remaining minimum system information (RMSI), or othersystem information (OSI). If the reserved resources 215 are used forPRACH, base station 105-a may transmit an indicator 220 for the PRACHresources. UE 115-a may then determine that a CCA gap is in a symbolperiod adjacent to a beginning symbol period of the indicated PRACHresources, to permit performance of a CCA procedure immediately prior tothe beginning symbol period of the PRACH resources. For a CCA gaplocated between data and control channels (e.g., PUSCH and a reservedresource of PUCCH), the OSI may configure the UE 115-a with whichresources to rate match around (e.g., rate match around control channeland a CCA gap).

If the reserved resources 215 are UE-specific, the base station 105-amay use RRC signaling to indicate the reserved resources 215 to the UE115-a, and hence the indicated reserved resources 215 may beUE-specific. For example, reserved resources for PRACH, PUCCH, etc. maybe indicated to UE 115-a in UE-specific RRC signaling, and UE 115-a mayrate match PUSCH around the indicated reserved resources 215.

In some cases, a DMRS may be scheduled to be transmitted during at leasta portion of the time and frequency resources of the reserved resources215. FIG. 5 illustrates different techniques for handling the collisionsof DMRS and the reserved resources 215. In some cases, base station105-a may schedule two consecutive RACH occasions within a reservedresource set. Techniques related to the consecutive RACH occasions aredescribed in more detail in FIGS. 6 and 7. In some cases, a UE 115 inthe wireless communications system 200 may implement techniques formultiple sensing occasions in an uplink burst. These techniques aredescribed in more detail in FIGS. 8, 9, 10, and 11.

In some cases, the techniques described herein may lead to someadvantages for a UE 115 and base station 105. For example, by ratematching an uplink shared data channel transmission around reservedresources, throughput may on uplink shared channels be increased. Thesetechniques may support the UE 115 to meet stringent reliability andlatency conditions for some types of communications (e.g., URLLC) whilestill providing high throughput for other types of communications.Moreover, internal components of the UE 115 applying the techniques mayimprove power utilization by improving spectral efficiency such that theUE 115 performs fewer CCA procedures, which may reduce power consumptionfor components in the UE 115. Additionally, the techniques of providingCCA gaps between (e.g., and before) RACH occasions may increase spectralefficiency, throughput, and latency considerations, as the UE 115 mayhave increased likelihood to gain control of the transmission medium.

FIG. 3 illustrates an example of a resource allocation scheme 300 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. In some examples, resourceallocation scheme 300 may implement aspects of wireless communicationssystem 100.

The resource allocation scheme 300 shows an uplink resource allocation305, which is an example of an uplink resource allocation to a UE 115 asdescribed in FIG. 2. The base station 105 may, for example, transmit agrant to UE 115 indicating the uplink resource allocation 305 within ashared radio frequency spectrum band. The uplink resource allocation 305may span a frequency allocation 325 that includes a portion of, or oneor more, resource blocks in frequency and one or more TTIs (e.g., one ormore slots 330) in time. The UE 115 may transmit a PUSCH transmission tothe serving base station within the uplink resource allocation 305.

In some cases, reserved resources (e.g., the reserved resources 310) mayoverlap the uplink resource allocation 305, and the UE 115 may ratematch an uplink transmission around the reserved resources 310. When theUE 115 rate matches around the reserved resources 310, the UE 115 doesnot transmit within the reserved resources 310, even if the uplinkresource allocation indicates that the overlapping resource is allocatedto the UE 115. As described in FIG. 2, the reserved resources 310 may beused for PRACH, PUCCH, SRS, etc. In the depicted example, the reservedresources 310 may be in the middle of the uplink resource allocation305, and the UE 115 may rate match an uplink transmission around thereserved resources 310 (e.g., transmit uplink data using the otherresource elements within the uplink resource allocation 305).

In some cases, the reserved resources 310 may be in the middle or theend of the slot 330, and the UE 115 may leave a gap for a CCAopportunity (e.g., a CCA gap 315) so other UEs 115 may contend to usethe reserved resources 310. The CCA gap 315 may be between or beforerandom access resources. The CCA may be a contention-based accessprocedure such as LBT. In some cases, the base station 105 may transmita grant indicating that up to the full slot the slot 330 is allocated tothe UE 115 for data transmission. The UE 115 may receive an indicationof the reserved resources 310, determine that the full slot is allocatedto the UE 115, and autonomously determine not to transmit within atleast one symbol period that occurs prior to the reserved resources 310(e.g., immediately prior). The blank symbol period may be referred toherein as a CCA gap 315. In some cases, even though a grant allocatesthe full slot to the UE 115, the UE 115 may determine to refrain fromtransmitting during the symbol period adjacent to the reserved resources310 so that the adjacent symbol period may be used as the CCA gap 315.In some cases, the duration of CCA gap 315 may be more than one symbol,such as two symbols etc., where the duration of the gap 315 may beselected to provide sufficient time to enable performing of CCA withacceptable success rates.

In some cases, the reserved resources 310 may be occur at a beginning ofthe slot 330 (e.g., within a first, beginning, symbol period of the slot330). To account for this location within slot 330, the base station 105may control the behavior of the UE 115 via grants. For example, the basestation 105 may ensure that a previous grant does not allocate a symbolperiod occurring immediately prior to a first symbol period of slot 330,so that the unallocated symbol period may be used as a CCA gap 315 forreserved resources 310 occurring at a beginning of slot 330.

In some cases, the UE 115 may refrain from transmitting in a symboloccurring prior to the reserved resources 310 even if the grant does notexplicitly indicate to leave that symbol period blank. In some otherexamples, the UE 115 may follow the grant and leave the symbol periodprior to the reserved resources 310 blank only if indicated to do so inthe grant or if the base station 105 otherwise indicates to do so.

After a last symbol period of the reserved resources 310, the UE 115 mayperform another CCA prior to resuming transmission in a next symbolperiod. For example, the UE 115 may not transmit using a portion of thetransmission of its uplink resource allocation 305 in one or more symbolperiods due to the reserved resources 310 occupying that portion. Thatportion of the transmission bandwidth may be seen as available after alast symbol period of the reserved resources 310. The UE 115 may performa CCA after a last symbol period of the reserved resources 310, forexample at symbol period 340, to regain access to the shared radiofrequency bandwidth for that portion of bandwidth.

By rate matching around the reserved resources 310 and the CCA gap 315,the UE 115 may transmit an uplink transmission (e.g., PUSCHtransmission) on any resources within its uplink resource allocation 305except the reserved resources 310 and the CCA gap 315. The UE 115 doesnot transmit on the reserved resources 310 or the CCA gap 315, so thatthe UE 115 does not interfere with other UEs performing a CCA procedurewithin the CCA gap 315 or transmissions using the reserved resources310.

The UE 115 may identify the rate matching configurations for thereserved resources 310 and the CCA gap 315 as described in FIG. 2. Forexample, the serving base station 105 may transmit an explicit orimplicit indicator of the reserved resources 310 and of the CCA gap 315.In some cases, the rate matching configurations for the reservedresources 310 and the CCA gap 315 may be indicated differently. Forexample, the reserved resources 310 may be explicitly indicated, and theUE 115 may implicitly identify the CCA gap 315 based on the time andfrequency resources of the reserved resources 310.

FIG. 4 illustrates an example of a resource allocation scheme 400 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. In some examples, resourceallocation scheme 400 may implement aspects of wireless communicationssystem 100.

Resource allocation scheme 400 shows a uplink resource allocation 405spanning a bandwidth 425 and a time duration 420. The base station 105may transmit a grant to the UE 115 indicating the uplink resourceallocation 405 that allocates time and frequency resources to the UE 115for sending an uplink transmission, as described in FIG. 2. In somecases, the time duration 420 may be multiple slots, and the bandwidth425 may be multiple resource blocks. Further, the reserved resources 410may occupy a subset of resource blocks within the bandwidth 425 for aportion of the time duration 420 (e.g., number of symbol periods or, insome cases, a number of slots). In some cases, the reserved resources410 may collide or overlap with channels other than data channels. Forexample, the reserved resources 410 may overlap with a control channelsuch as PUCCH. If two different allocations collide or overlap, the twodifferent allocations share the same time and frequency resources.

In some examples, the reserved resources 410 may occupy a portion of thebandwidth 425 such that the UE 115 cannot transmit uplink data in thatportion of the bandwidth 425. In some cases, the UE 115 may skip uplinktransmission in the symbol periods that include the reserved resources410 (e.g., skip PUSCH transmission if OCB criteria is not met). In someother examples, the UE 115 may still transmit in the unreserved portionof the bandwidth during a time duration that also includes the reservedresources 410 (e.g., shown as the uplink resource allocation 405-b belowthe reserved resources 410).

The UE 115 may have a number of options of how it operates within afirst symbol period occurring after a last symbol period of the reservedresources 410. In an example, the UE 115 may perform a CCA procedure ifthe UE 115 begins transmitting using a different bandwidth size afterthe reserved resources 410. For example, the UE 115 may be configured toleave CCA gaps post the reserved resources 410 if a bandwidth of therate matched uplink transmission changes after the reserved resources410. Thus, in some cases, the UE 115 may leave a CCA gap 415 after thereserved resources and perform a CCA procedure during the CCA gap 415when attempting to use the full bandwidth 425 (or a bandwidth thatdiffers from the remaining bandwidth 430), because the UE 115 did notuse the full bandwidth 425 due to the reserved resources 410. The UE 115may determine whether to transmit on the reserved resources 410 oruplink resource allocation 405 based on the CCA gap 415.

In some other examples, the UE 115 may rate match an uplink transmissionto use remaining bandwidth 430, which is the portion of bandwidth 425that does not include the reserved resources 410. In some cases, the UE115 may skip performing a CCA procedure if the UE 115 continues to usethe same bandwidth before, during, and after the reserved resources 410.In some examples, the UE 115 may start using the portion of thebandwidth 425 corresponding to the reserved resources 410 withoutperforming an LBT after a last symbol period of the reserved resources410. The UE 115 may select which option to perform or be configured withwhich option to select by the base station 105 based on, for example,the duration and/or bandwidth of the reserved resources 410. It is notedthat the reserved resources 410 may collide with other channels (e.g.,PUCCH) instead of or in addition to a PUSCH, and the UE 115 may ratematch an uplink transmission (e.g., a PUCCH transmission, a PUSCHtransmission, or both) around the reserved resources 410 and any CCAgaps 415.

When the UE 115 reduces its transmission bandwidth to avoid the reservedresources 410, the UE 115 may boost its transmission power over theremaining transmission bandwidth 430. The power boost may be performedsuch that the total power transmitted in the remaining transmissionbandwidth 430 (e.g., the non-reserved resource bandwidth) is equal tothe total power transmitted over the entire bandwidth 425. Thus, the UE115 may transmit on uplink resource allocation 405-b using up to thesame transmission power as what was used to transmit over the largerbandwidth of uplink resource allocation 405-a and/or 405-b. Based onuplink resource allocation 405-b having a smaller transmissionbandwidth, a transmission within uplink resource allocation 405-b mayhave a higher PSD as compared to a transmission within uplink resourceallocation 405-a or 405-c. The PSD for uplink resource allocation 405-bmay still be within PSD regulations.

The UE 115 determine whether to indicate that it is boosting itstransmission power based on which modulation scheme is being used forthe uplink rate matched transmission. If the UE 115 transmits using aquadrature amplitude modulation (QAM) configuration (e.g., 16 QAM orhigher), the UE 115 may indicate the power boost to the base station 105for demodulating the transmission. However, if the UE 115 transmitsusing binary phase shift keying (BPSK) and/or quadrature phase shiftkeying (QPSK) modulation, the UE 115 may skip indicating the powerboost. In some cases, the base station 105 may indicate to the UE 115how much to power boost in a DCI or RRC configuration.

FIG. 5 illustrates examples of collision response schemes 500 thatsupport shared channel design around reserved resources in accordancewith aspects of the present disclosure. In some examples, the collisionresponse schemes 500 may implement aspects of wireless communicationssystem 100.

In some cases, reserved resources may collide with resources allocatedfor a DMRS transmission by the UE 115 (e.g., a DMRS transmission isscheduled within at least a portion of the reserved resources). The UE115 may identify the collision and perform a collision response to avoidthe collision. Examples of various different collision responses areshown in FIG. 5. Collision response schemes 500-a to 500-d depictexamples of where to transmit a DMRS 510 when a collision is identified.

The selected collision response among collision response schemes 500-ato 500-d may be based on a number of DMRS symbols configured, a numberof colliding DMRS symbols, a waveform (e.g., OFDM, single carrier(SC)-OFDM, etc.) used for the uplink transmission, explicit signaling indownlink control information, whether the symbol is a blank symbol or asymbol with a reserved resource, or a type or purpose of the reservedresource (e.g., PUCCH, SRS, etc.).

The collision response schemes 500-a to 500-d may indicate differentreference signal patterns (e.g., DMRS patterns) corresponding todifferent configurations in which a DMRS transmission may be transmittedwithin a TTI 525 (e.g., a slot) relative to reserved resources 505. Insome cases, a reference signal pattern for a DMRS transmission may bethat the DMRS 510 is transmitted in pairs of symbols (e.g., codedivision multiplexed (CDM) across two symbols). If the reference signalpattern includes a pair of symbols, the following techniques may beapplied to both symbols or only one of the symbols of the pair. In somecases, the collision response schemes 500-a to 500-d may be applied totwo or more symbols of the reference signal pattern and a decisionwhether to apply at least one of the collision response schemes 500-a to500-d may be a function a distance between pairs of DMRS symbols. Forexample, moving one of the DMRS symbols in the pair may be permitted ifa distance between the pair of DMRS symbols is less than a predeterminedthreshold. Otherwise, both symbols may be moved.

In collision response scheme 500-a, there are four RBs 520-a to 520-dreserved as the reserved resources 505. In some cases, there may be oneor more intervening RBs between each of the RBs 520 the reservedresources 505, separating RBs 520-a to 520-a in frequency. The one ormore RBs 520 overlap uplink resources 515 within a TTI 525. The TTI 525may include one or more slots. In collision response scheme 500-a, theUE 115 may identify that a DMRS 510 is scheduled for transmission in asymbol period 540 that also includes the reserved resources 505 in RBs520-a to 520-d. The UE 115 may skip transmitting the DMRS 510 in anyresources where a scheduled DMRS transmission collides with the reservedresources 505. The UE 115 may transmit the DMRS 510 in symbol period 540on interlaces (e.g., tones) corresponding to the intervening RBs whichdo not collide with the reserved resources 505 and skip transmitting theDMRS 510 on resources that do collide. As shown, the UE 115 does nottransmit the DMRS 510 on the RBs which overlap with the reservedresources 505. The UE 115 does transmit on RBs 520 of the uplinkresources 515 which do not overlap with the reserved resources 505. Insome examples, when the reserved resources 505 use a tone interlacestructure, the reference signal pattern (e.g., the DMRS pattern) onthose symbols may use the unreserved tone level interlaces or at leastdata can be transmitted in the un-reserved tones.

In collision response scheme 500-b there are four RBs 520-a to 520-dindicated to be reserved as the reserved resources 505. In some cases,there may be one or more intervening RBs between each of the RBs 520 thereserved resources 505, separating RBs 520-a to 520-a in frequency. Theone or more RBs 520-a to 520-a overlap uplink resources 515 within a TTI525. The TTI 525 may include one or more slots. In collision responsescheme 500-b, the UE 115 may skip transmitting the DMRS 510 on anysymbol period in which DMRS is scheduled to be transmitted that overlapswith at least one symbol period of the reserved resources 505. As shown,if the UE 115 is scheduled to transmit a DMRS 510 during a symbol period540, the UE 115 skips transmitting the DMRS 510 in symbol period 540because reserved resources 505 are included within symbol period 540.

In collision response scheme 500-c there are four RBs 520-a to 520-dreserved as the reserved resources 505. In some cases, there may be oneor more intervening RBs between each of the RBs 520 the reservedresources 505, separating RBs 520-a to 520-a in frequency. In someexamples, shown by 500-c, the UE 115 may shift in which symbol period aDMRS 510 is transmitted to immediately after a last symbol period of thereserved resources 505. After the last symbol of the reserved resources505, the UE 115 may transmit the DMRS 510 using all of the allocatedfrequency resources in the uplink resources 515 during symbol period545. In some cases, the UE 115 may maintain a defined gap (e.g., minimumgap) between each symbol period within a slot that includes a DMRStransmission. For a slot that includes multiple DMRS transmissions, theUE 115 may adjust in which symbol period a first DMRS transmission isscheduled to be transmitted and determine if the adjusted symbol periodimpacts the gap spacing relative to any other DMRS transmission. In somecases, the UE 115 may also adjust in which symbol period a second DMRStransmission is scheduled to be transmitted based on the adjusted symbolperiod for the first DMRS transmission. For example, a DMRS transmissionmay be shifted over by one or more symbol periods from symbol period 550to 555 to maintain gap between DMRS transmissions in symbol periods 545and 555.

In collision response scheme 500-d there are four RBs 520 520-a to 520-dreserved as the reserved resources 505. In some cases, there may be oneor more intervening RBs between each of the RBs 520 the reservedresources 505, separating RBs 520-a to 520-a in frequency. In collisionresponse scheme 500-d, the UE 115 may shift colliding DMRS transmissionsto a later symbol, and transmit non-colliding DMRS transmissions intheir originally scheduled resources. For example, a DMRS transmissionmay be originally scheduled for transmission in symbol period 540. TheUE 115 may transmit the non-colliding DMRS transmissions in theiroriginally scheduled resources within symbol period 540. The DMRStransmissions which collide with the reserved resources 505 may beshifted to a symbol period (e.g., symbol period 560) that occurs afterthe reserved resources 505 (e.g., in a symbol period that occursimmediately after a last symbol period that includes the reservedresources 505). In some cases, the UE 115 may also shift a second DMRStransmission within the TTI 525 to maintain the gap 530 relative to aDMRS transmission in symbol period 560.

In some cases, when a scheduled DMRS transmission collides with areserved resource, the UE 115 may have a number of options of whichcollision response to select, including dropping an uplink transmission(e.g., PUSCH transmission) in a current TTI and sending the droppeduplink transmission in a subsequent TTI, or dropping the scheduled DMRStransmission, or transmitting the scheduled DMRS transmission ignoringthe reserved resources 505 (e.g., base station 105 makes transmissionson the reserved resources orthogonal to the DMRS transmission, permitsthe resulting interference to occur, etc.), or shifting the scheduledDMRS transmission to another symbol, or the like. The option performedby UE 115 may be selected based on number of DMRS symbols configured, ora waveform type of the uplink transmission, or downlink controlinformation (DCI) indicating which option to select, or a type of thereserved resources 505, or the like.

In some additional examples, dropping a DMRS transmission in aparticular symbol period may be permitted if multiple symbols areconfigured for DMRS transmission. The vacated symbol could be used totransmit data (e.g., if it is not a blank symbol for a CCA gap). In somecases, a scheduled DMRS transmission may be moved (e.g.,preponed/postponed) to symbols where there are no collisions with thereserved resources. Again, the vacated symbol could be used to transmitdata (e.g., if it is not the blank symbol). In some examples, DMRS maybe transmitted on resources (e.g., interlaces/RBs) which do not collidewith the reserved resources and skipped for resources that collide. Forresources (e.g., interlaces/RBs) where DMRS is skipped, a DMRS 510 maybe transmitted on subsequent symbols. If the UE has multiple DMRSpattern options, the UE 115 may select among them based on a definedordering (e.g., pre-determined ordering) to avoid collision of DMRS withthe reserved resources, blank symbols, or both, and the selection mayalso be based on information in uplink grant DCI. In some cases, theselected option among these at any given time may depend on the numberof DMRS symbols configured, number of colliding DMRS symbols, a waveform(e.g., OFDM/SC-FDM) being used for UL, explicit signaling in DCI,whether symbol is blank symbol or symbol with reserved resource,type/purpose of the reserved resource, or the like, or any combinationthereof.

FIG. 6 illustrates an example of a back to back RACH occasion 600 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. In some examples, back to backRACH occasion 600 may implement aspects of wireless communicationssystem 100.

As described in FIG. 2, a base station 105 may indicate reservedresources to the UE 115. In some examples, the reserved resources may beused for RACH communications. In the depicted example, the reservedresources may include two back to back RACH occasions 605, where RACHoccasion 1 605-a is immediately followed by RACH occasion 2 605-b. Forexample, if a RACH message is 6 symbols long, the base station 105 mayschedule a first RACH occasion on symbols 0 to 5 of a slot and a secondoccasion on symbol 6 to 11. In some examples, there may be a CCA 610 gapbetween RACH occasion 1 605-a and RACH occasion 2 605-b.

In an example, UE 115-c may be assigned RACH occasion 605-a and UE 115-dmay be assigned RACH occasion 605-b. UE 115-c may perform a CCA 610-aprior to transmitting a RACH message 615, pass the CCA 610-a, andtransmit the RACH message 615. The RACH message 615 may include, forexample, a random access preamble transmission with a RACH occasion 605.

However, based on the RACH occasions 605 being immediately consecutive,the RACH message 615 may be sensed by UE 115-d when UE 115-d performsCCA 610-b. Thus, UE 115-d may fail the CCA 610-d, and UE 115-d may nottransmit its RACH message at 620. UE 115-c, by transmitting on the firstRACH occasion 1 605-a, causes interference that UE 115-d detects duringits CCA 610-b, thereby preventing UE 115-d from using the second RACHoccasion 605-b. To avoid this issue and to provide fair access to eachof the RACH occasions 605, the base station 105 may implement techniquesas described in FIG. 7 to include CCA gaps between each RACH occasion605.

FIG. 7 illustrates an example of a back to back RACH occasion 700 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. In some examples, back to backRACH occasion 700 may implement aspects of wireless communicationssystem 100.

A base station 105 may indicate to a UE 115 reserved resources that mayinclude multiple RACH occasions 705, such as reserved RACH occasion705-a, and RACH occasion 705-b. To give each of UE 115-e and 115-f afair opportunity to use a respective one of the RACH occasions 705, thebase station 105 may include a gap (e.g., of at least one symbol period)between RACH occasion 705-a and 705-b so that UE 115-f may perform a CCA715 and attempt to transmit using the RACH occasion 705-b. In theillustrated example, there may be two RACH occasions 705 (e.g., RACHoccasion 705-a and RACH occasion 705-b separated by the CCA gap 710).However, in other examples, there may be additional RACH occasions, eachof which may be separated by a CCA gap 710. In some cases, the basestation 105 may configure a CCA gap 710 between each of the RACHoccasions 705. Or, in some cases, the UEs 115 may treat the RACHoccasions 705 as though there is a CCA gap 710 configured between theRACH occasions 705. Therefore, the base station 105 may not configure orperform any signaling to indicate the CCA gap 710, but the UEs 115 mayidentify a CCA gap 710 and, in some cases, perform a CCA procedureduring the CCA gap 710 between the RACH occasions 705. A UE 115 may thentransmit in the following RACH occasion 705 based on a result of the CCAprocedure.

In some implementations, a RACH format (e.g., a PRACH format) mayspecify a cyclic prefix (CP) duration and a number of symbol durationsto use for PRACH. In some cases, a PRACH format's guard time may be zeroor non-zero. A guard time for a PRACH format may be selected such that acombination, or sum, of the guard time, PRACH CP duration, and PRACHsymbol duration is an integer multiple of symbol durations. The guardtime may be less than a symbol duration in length. In some cases, theremay be a gap between the RACH occasions 705-a and 705-b. In someexamples, RACH occasions may be integer number of OFDM symbols,including the OFDM CP. in some cases, each RACH occasion may include aRACH CP duration, more than one RACH symbols, and a guard time.

The gap between the between the RACH occasions 705-a and 705-b may beconfigurable. The gap may be configurable to a guard time which may beless than one symbol duration including a gap in units of integer numberof symbols. The UE may implicitly assume a gap of the guard time whichmay be less than one symbol duration including a gap in some integernumber of symbols when operating in unlicensed spectrum as opposed towhen operating in licensed spectrum. The gap may be chosen to be largerthan the minimum defer period for some LBT configurations (e.g., acategory-4 LBT) including a determined number of CCA slots. In somecases, UE 115 may determine whether to transmit using the RACH occasion705-b based on the CCA 715.

In an example, UE 115-e may perform CCA 715-a, passes, and transmitsRACH message 720-a to the base station 105. UE 115-f performs CCA 715-band, due to the CCA gap 710, passes without detecting the RACH message720-a transmitted by UE 115-e. UE 115-f may then transmit the RACHmessage 720-b during RACH occasion 705-b. Thus, each of UE 115-e and UE115-f may respectively use RACH occasions 705-a and RACH occasion 705-bwithout a transmission in the earlier RACH occasion 705-a interferingwith a CCA procedure performed by UE 115-f when attempting to use thelater RACH occasion 705-b.

In some examples, the UE 115 may interpret a RACH resource configurationas having a gap if there are two or more back to back RACH occasions705. For example, the base station 105 may transmit a configurationmessage that configures the UE 115 with at least two back to back PRACHoccasions 705 each having a length of a defined number of symbols (e.g.,format A3 has a length of 6 symbols) and indicates a one symbol gapbetween each pair of RACH occasions 705 (e.g., at symbol period 6). TheUEs 115 may process the configuration message to determine that thefirst RACH occasion 705-a is on symbols 0 to 5, the second RACH occasion705-b is on symbols 7 to 12, and may assume that symbol 6 is left blankfor the CCA gap 710. In this way, the base station 105 may maintain theRACH configuration by adding additional CCA gap configurations ifappropriate. The base station 105 may also have flexibility to configurean additional CCA gap period 710 (e.g., based on a blocking probabilityof a transmission in a first RACH occasion 705 blocking a CCA performedfor a second RACH occasion 705).

In some cases, RACH occasions with CCA may extend beyond a current slotand into a next slot. For example, a RACH format such as A1 may have 6RACH occasions in a slot, where each occasion is 2 symbols long. If a UE115 identifies 1 symbol CCA gap between each RACH occasion, some RACHoccasions (e.g., the last 2) may spill into the next slot. If the RACHoccasions begin in slot 725-b, the last two RACH occasions may be at thestart of slot 725-c. If RACH occasions spill into the next slot, thebase station 105 may transmit a broadcast message configuring UE 115whether to use RACH occasions that occur in a next slot. In some otherexamples, the UEs 115 may not use the RACH occasions that spill into thefollowing slot. Or, in some examples, the UEs 115 may transmit on theRACH occasions that spill into the next slot if a TTI type indicator, asubframe format indicator (SFI), or the like, received from the basestation 105 indicates that the next slot is also used for uplinktransmission.

Additionally, or alternatively, to the techniques for a CCA gap betweenRACH occasions, a base station 105 may support a UE 115 to start RACHtransmission at a later time based on an LBT outcome. In some cases, theUE 115 may use the earliest symbol period where the LBT passes as astarting point for the RACH transmission. For example, if a RACHoccasion is configured for symbols 6-11, base station 105 may allow UE115 to start transmitting the RACH at symbols 7, 8, or 9 in addition toor instead of starting at symbol 6 but still end RACH transmission atsymbol 11. The UE 115 may transmit, for example, by puncturing theportion of the RACH occasion that the UE 115 is able to transmit.

If the UE 115 transmits fewer RACH symbols due to LBT failure at a firstsupported starting point, the UE 115 may transmit the RACH at a higherpower than what would have been used had the UE 115 transmitted for upto all of the RACH symbols. For example, the transmit power may beincreased by a factor based on a maximum number of PRACH symbols and theactual number of PRACH symbols transmitted. For example, the factor maybe based on the maximum number of PRACH symbols divided by the actualnumber of PRACH symbols transmitted. Due to the multiple possiblestarting points within a RACH occasion, the UE 115 may transmit RACH onback to back RACH occasions without blocking other UEs 115.

FIG. 8 illustrates an example of a multiple CCA sensing occasion scheme800 that supports shared channel design around reserved resources inaccordance with aspects of the present disclosure. In some examples,multiple CCA sensing occasion scheme 800 may implement aspects ofwireless communications system 100.

A base station 105 may schedule a UE 115 for uplink transmissions withinthe base station transmission opportunity (TxOP) (e.g., an amount oftime the base station 105 is allowed to use a shared radio frequencyspectrum band after passing CCA). For example, downlink subframe 805-amay include a grant scheduling the UE 115 with resources in uplinksubframes 810-a and 810-b, and downlink subframe 805-b may include agrant scheduling the UE 115 with resources in uplink subframes 810-c and810-d. The UE 115 may have a subcarrier spacing of 15 kHz, where eachsubframe is 1 ms long. In the following example, the UE 115 is scheduledn=4 consecutive uplink frames.

When an uplink transmission is scheduled within the base station TxOP,the number of single-shot CCA attempts (e.g., single-shot LBT attempts)by a UE 115 within the shared base station channel occupancy time (COT)may be based on the number of consecutively allocated uplink subframes810. For example, if the UE 115 is allocated n consecutive uplinksubframes 810 of length 1 ms, the UE may be limited to n+1 single-shotCCA attempts, where n is a positive integer. The consecutive uplinksubframes may provide the UE 115 with 2n possible starting positions815. As depicted, eight vertical lines represent the 2n=8 possiblestarting locations for the four uplink TTIs 810-a to 810-d (e.g., uplinksubframes). The limit to n+1 single-shot CCA attempts may applyregardless of a number of or a type of grants that were used to schedulethe consecutive uplink subframes. The limit to n+1 single-shot CCAattempts also may apply for cases where there may be gaps of one symbolor less between the consecutively allocated subframes.

As a wireless communications system may use different SCS, the number ofslots that occur within a defined time duration increases as the SCSincreases. Therefore, there is a larger number of potential startingpositions 815 and single-shot CCA opportunities for UEs 115 with ahigher SCS, as compared to the number of single-shot CCA opportunitiesfor UEs 115 with a higher SCS. FIGS. 9-11 describe techniques ofselecting a number of single shot LBT attempts for UEs 115 withdifferent SCS.

FIG. 9 illustrates an example of a multiple CCA sensing occasion scheme900 that supports shared channel design around reserved resources inaccordance with aspects of the present disclosure. In some examples,multiple CCA sensing occasion scheme 900 may implement aspects ofwireless communications system 100.

Some wireless communications systems may support multiple different SCS.For example, wireless communications systems 100 and 200 may use 15 kHzSCS, 30 kHz SCS, and 60 kHz SCS. Slot with a larger SCS may be shorterin time. Thus, there may be four 30 kHz uplink slots 915 (e.g., 30 kHzuplink slots 915-a, 915-b, 915-c, and 915-d) in the same time durationof two 15 kHz uplink slots 905 (e.g., 15 kHz uplink slots 905-a and905-b). The 15 kHz uplink slots 905-a and 905-b may each occupy 1 ms,while two 30 kHz uplink slots 915 occupy 1 ms. Therefore, the 30 kHzuplink slots 915 may have twice as many CCA candidate locations 920, ascompared to the candidate locations 910 for the 15 kHz uplink slots 905,in the same amount of time.

The base station 105, the UE 115, or both, may implement techniques toconfigure both the 15 kHz UE 115 and the 30 kHz UE 115 with a set of CCAlocations. For example, the base station 105 may configure each UE 115(e.g., including those of different SCS) with a set of n+1 CCA locationswithin the consecutive uplink slots when the base station 105 grants theuplink burst of n milliseconds. For example, if n is 2, this maycorrespond to two 15 kHz slots and four 30 kHz slots, but both the 15kHz configuration and the 30 kHz configuration are configured with 3(e.g., n=2, 2+1=3) CCA locations.

In some cases, the base station 105 configure each UE 115 to leave a gapbefore each of the n+1 selected locations and to perform a CCA at eachof the n+1 selected locations. A UE 115, once CCA determines that theshared radio frequency spectrum band is available, may continue totransmit until the end of the set of consecutive slots withoutperforming a CCA at the subsequent CCA locations as shown in FIG. 11. InFIGS. 10 and 11, the 1st, 2nd, and 4th candidate locations 910 (e.g.,candidate locations 910-a, 910-b, and 910-c respectively) are selectedfor the lower SCS configuration. This corresponds to the 1st, 3rd, and7th candidate locations 920 of the higher SCS configuration (e.g.,candidate locations 920-a, 920-b, and 920-c). Thus, each configurationhas 3 locations for a single-shot CCA, despite the two configurationshaving different SCS.

FIG. 10 illustrates an example of a multiple CCA sensing occasion scheme1000 that supports shared channel design around reserved resources inaccordance with aspects of the present disclosure. In some examples,multiple CCA sensing occasion scheme 1000 may implement aspects ofwireless communications system 100.

As described in FIGS. 8 and 9, a base station 105 may transmit a grantfor uplink TTI 1010-a (e.g., uplink subframe) in downlink TTI 1005-a(e.g., downlink subframe) and a grant for uplink TTI 1010-b in downlinkTTI 1005-b. The uplink TTIs 1010 may be to uplink subframes used foruplink transmissions by UE 115-h and UE 115-g. In the shown example, theUEs 115 are configured with the same single-shot CCA locations 1015-a to1015-c within the uplink subframes. Thus, the UEs 115 perform a CCAprocedure at each of the CCA locations 1015-a to 1015-c so as to notcause UE to UE interference (e.g., UE to UE blocking). The single-shotCCA locations 1015 may be configured when the base station 105 grantsthe uplink burst including the two uplink TTIs 1010. In some cases, anuplink TTI 1010 may be an example of a subframe.

UE 115-g and UE 115-h may perform a first CCA 1020 at the same timecorresponding to CCA location 1015-a. In an example, the CCA 1020performed by UE 115-g may pass, and the CCA 1020 performed by UE 115-hmay fail. UE 115-g may transmit an uplink transmission 1025 in afollowing uplink slot, and UE 115-h may not transmit in the followinguplink slot at 1030 due to the CCA procedure failure. However, at thenext single-shot CCA location 1015, both UEs 115 may again performanother CCA 1020 and both UEs 115 may gain access to the shared radiofrequency spectrum band. Both UEs 115 may then transmit uplinkinformation in the following uplink slots.

In this example, although UE 115-h failed the first LBT, UE 115-h hadanother opportunity to gain access to the transmission medium at thenext single-shot CCA location 1015. The aligned LBT gaps may prevent UEto UE blocking with the same base station 105. In some cases, if a UEpasses CCA in a previous CCA location 1015, the UE still needs toperform another CCA procedure in a later CCA location 1015.

In some cases, a UE that obtains a shared radio frequency spectrum bandat a particular CCA location may transmit without performing a CCA atthe subsequent CCA locations. FIG. 11 illustrates an example of amultiple CCA sensing occasion scheme 1100 that supports shared channeldesign around reserved resources in accordance with aspects of thepresent disclosure. In some examples, multiple CCA sensing occasionscheme 1100 may implement aspects of wireless communications system 100.

As described in FIGS. 8, 9, and 10 a base station 105 may transmit agrant for uplink TTI 1110-a in downlink TTI 1105-a and a grant foruplink TTI 1110-b in downlink TTI 1105-b. The uplink TTIs 1110 may besubframes used for uplink transmissions by UE 115-i and UE 115-j. In theshown example, the UEs 115 are configured with the same single-shot CCAlocations 1115 within the uplink subframes. Thus, the UEs 115 performCCA at the same time as to not cause UE to UE interference. Thesingle-shot CCA locations 1115 may be configured when the base station105 grants the uplink burst including the two uplink TTIs 1110.

UE 115-i and UE 115-j may perform a first CCA 1120 at the same time.Once a UE obtains a shared radio frequency spectrum band at a particularCCA location, that UE may transmit for a remainder of the uplink slotsindicated in the grant without performing a CCA at the subsequent CCAlocations. In an example, the CCA 1120 performed by UE 115-g may pass atCCA location 1115-a, and the CCA 1120 performed by UE 115-h at CCAlocation 1115-a may fail, for example due to an interfering packet 1135(e.g., from a wireless device using Wi-Fi). UE 115-g may transmit anuplink transmission 1125 for the remainder of the consecutive uplinkTTIs 1110-a and 1110-b without performing a CCA at the followingsingle-shot CCA locations 1115-b or 1115-c. The transmission from UE115-i during the time periods in which UE 115-j performs a CCA in CCAlocations 1115-b and 1115-c may cause the CCAs 1120 to fail at thefollowing single-shot CCA locations 1115-b and 1115-c. Thus, UE 115-imay have improved throughput, but UE 115-j may not gain access to thetransmission medium for the uplink burst due to transmissions on theshared radio frequency spectrum band by UE 115-i.

Thus, when a UE 115 is granted multiple slots for transmission under abase station TXOP, for fair channel access, a UE 115 may be limited ton+1 CCA locations within a defined time duration (e.g., n ms), and hencethe n+1 number of CCA locations may be a function of time andindependent of the SCS. The position of the n+1 number of CCA locationsmay be at the start or middle of sub-frames according the respective SCSvalues. In some examples, the base station may let each UE 115 decidewhich n+1 CCA locations to use. In another example, the base station 105may configure each UE with the same n+1 locations when granting a uplinkburst of n ms. In some examples, the base station 105 may configure eachUE 115 to leave a gap before each of these n+1 CCA locations and toperform CCA at each of the n+1 CCA locations. In this example, each UE115 may leave a CCA gap and perform a CCA procedure at each of the n+1CCA locations. In some examples, the base station 105 not specify thateach UE is to leave a CCA gap before each of the n+1 CCA locations. Insuch an example, once a UE 115 obtains the shared radio frequencyspectrum band, the UE 115 may continue to transmit till end of the burstgrant without leaving any CCA gaps.

The technique of FIG. 11 may permit UEs to use any of the n+1 CCAlocations to acquire the shared radio frequency spectrum band (e.g., ifno other UE jumped in earlier to previously acquire the shared band or aUE that jumped in earlier is a hidden node). In some examples, guidanceon the n+1 CCA locations may be used to provide a time instance that mayprovide certain UEs potential CCA starting locations (e.g.,corresponding to different mini-slot boundary). Also, a later UE thatwas unable to acquire the shared radio frequency spectrum band at anearlier CCA location may optionally skip performing a CCA at subsequentCCA locations that may occurring during a middle of a PUSCH transmissionby a UE that acquired the shared band at the earlier CCA location.

FIG. 12 illustrates an example of a process flow 1200 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. In some examples, process flow 1200may implement aspects of wireless communications system 100. Processflow 1200 includes UE 115-k and base station 105-b, which may berespective examples of a UE 115 and a base station 105 as describedherein.

At 1205, base station 105-b may transmit an indicator of reservedresources in a shared radio frequency spectrum band. UE 115-k mayreceive the indicator of reserved resources. In some cases, at 1210, UE115-k may identify a location of a CCA gap relative to the reservedresources. In some cases, UE 115-k may identify locations of one moreCCA gaps. For example, there may be a CCA gap before the reservedresources and after the reserved resources. In some cases, the indicatorof reserved resources may identify a symbol period for each of the oneor more gaps. In some cases, base station 105-b may transmit anindicator of one or more CCA gaps identifying a symbol period for eachof the one or more gaps. In some cases, UE 115-k may receive theindicator of reserved resources and be configured to determine that aCCA gap occurs in a symbol period that is located before, after, orboth, relative to the location of the reserved resources. In an example,the reserved resources may occur in symbol periods 4-7, and the UE 115-kmay be configured to determine that a CCA gap occurs in symbol period 3,in symbol period 8, or both.

At 1215, UE 115-k may rate match an uplink shared data channeltransmission around the reserved resources. In some examples, UE 115-kmay rate match an uplink shared data channel transmission around the CCAgap. At 1220, UE 115-k may transmit, within the shared radio frequencyspectrum band, the rate matched uplink shared data channel transmission.UE 115-k may transmit the uplink shared data channel transmission afterrate matching around the reserved resources and, in some cases, the oneor more CCA gaps.

FIG. 13 illustrates an example of a process flow 1300 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. In some examples, process flow 1300may implement aspects of wireless communications system 100. Processflow 1300 includes UE 115-l and base station 105-c, which may berespective examples of a UE 115 and a base station 105 as describedherein.

At 1305, base station 105-c may transmit an uplink burst grantallocating uplink resources in a shared radio frequency spectrum bandfor a set of consecutive TTIs. In some examples, at 1310, base station105-c may transmit an indicator of a set of CCA locations within the setof consecutive TTIs, a number of the set of CCA locations being commonto multiple UEs 115 that respectively utilize TTIs having differentdurations.

At 1315, UE 115-l may perform at CCA at a first CCA location of the setof CCA locations and, at 1320, transmit, in the shared radio frequencyspectrum band, an uplink transmission within a TTI of the set ofconsecutive TTIs based on a result of successful CCA performed at one ofthe set of CCA locations. The UE 115-l may identify a successful CCA ifthe CCA indicates that the shared radio frequency spectrum band isavailable. In some examples, the UE 115-l may transmit, in the sharedradio frequency spectrum band, an uplink transmission within a firstsuccessful TTI of the set of consecutive TTIs based at least in part ona result of CCA performed at the set of CCA locations.

In some cases, UE 115-l may continue transmission for the set of theTTIs of the uplink burst grant without performing a CCA at subsequentCCA locations of the set of CCA locations based on determining that theshared radio frequency spectrum band is available at a prior CCAlocation of the set of CCA locations.

FIG. 14 shows a block diagram 1400 of a device 1405 that supports sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure. The device 1405 may be an example of aspects ofa UE 115 as described herein. The device 1405 may include a receiver1410, a communications manager 1415, and a transmitter 1420. The device1405 may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1410 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to sharedchannel design around reserved resources, etc.).

Information may be passed on to other components of the device 1405. Thereceiver 1410 may be an example of aspects of the transceiver 1720described with reference to FIG. 17. The receiver 1410 may utilize asingle antenna or a set of antennas.

The communications manager 1415 may receive an indicator of reservedresources in a shared radio frequency spectrum band, rate match anuplink shared data channel transmission around the reserved resources,and transmit, within the shared radio frequency spectrum band, the ratematched uplink shared data channel transmission.

The communications manager 1415 may also receive an uplink burst grantallocating uplink resources in a shared radio frequency spectrum bandfor a set of consecutive TTIs, receive an indicator of a set of CCAlocations within the set of consecutive TTIs, a number of the set of CCAlocations being common to a set of UEs that respectively utilize TTIshaving different durations, and transmit, in the shared radio frequencyspectrum band, an uplink transmission within a TTI of the set ofconsecutive TTIs based on a result of successful CCA performed at one ofthe set of CCA locations.

The communications manager 1415 may also receive an indicator of randomaccess resources in a shared radio frequency spectrum band, identify alocation of a CCA gap between a first random access resource of the setof random access resources and a second random access resource of theset of random access resources, perform a CCA procedure during the CCAgap and transmit, and determine whether to transmit on the second randomaccess resource based at least in part on a result of the CCA procedure.The communications manager 1415 may be an example of aspects of thecommunications manager 1710 described herein.

The communications manager 1415, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1415, or itssub-components may be executed by a general-purpose processor, a DSP, anapplication-specific integrated circuit (ASIC), a field-programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The communications manager 1415, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1415, or its sub-components, may be a separateand distinct component in accordance with various aspects of the presentdisclosure. In some examples, the communications manager 1415, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 1420 may transmit signals generated by other componentsof the device 1405. In some examples, the transmitter 1420 may becollocated with a receiver 1410 in a transceiver module. For example,the transmitter 1420 may be an example of aspects of the transceiver1720 described with reference to FIG. 17. The transmitter 1420 mayutilize a single antenna or a set of antennas.

FIG. 15 shows a block diagram 1500 of a device 1505 that supports sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure. The device 1505 may be an example of aspects ofa device 1405 or a UE 115 as described herein. The device 1505 mayinclude a receiver 1510, a communications manager 1515, and atransmitter 1555. The device 1505 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 1510 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to sharedchannel design around reserved resources, etc.). Information may bepassed on to other components of the device 1505. The receiver 1510 maybe an example of aspects of the transceiver 1720 described withreference to FIG. 17. The receiver 1510 may utilize a single antenna ora set of antennas.

The communications manager 1515 may be an example of aspects of thecommunications manager 1415 as described herein. The communicationsmanager 1515 may include a reserved resources indication receiver 1520,a CCA gap identifier 1525, a rate matching component 1530, a ratematched transmission component 1535, an uplink burst grant receiver1540, a CCA locations component 1545, and a consecutive uplinktransmission component 1550. The communications manager 1515 may be anexample of aspects of the communications manager 1710 described herein.

The reserved resources indication receiver 1520 may receive an indicatorof reserved resources in a shared radio frequency spectrum band. In somecases, the CCA gap identifier 1525 may identify a location of a CCA gaprelative to the reserved resources. The rate matching component 1530 mayrate match an uplink shared data channel transmission around thereserved resources. In some cases, the rate matching component 1530 mayrate match the uplink shared data channel transmission around the CCAgap. The rate matched transmission component 1535 may transmit, withinthe shared radio frequency spectrum band, the rate matched uplink shareddata channel transmission.

The reserved resources indication receiver 1520 may receive an indicatorof a set of random access resources in a shared radio frequency spectrumband. The CCA gap identifier 1525 may identify a location of a CCA gapbetween a first random access resource of the set of random accessresources and a second random access resource of the set of randomaccess resources. The CCA gap identifier 1525 perform a CCA procedureduring the CCA gap. The CCA gap identifier 1525 may determine whether totransmit on the second random access resource based on a result of theCCA procedure.

The uplink burst grant receiver 1540 may receive an uplink burst grantallocating uplink resources in a shared radio frequency spectrum bandfor a set of consecutive TTIs. The CCA locations component 1545 mayreceive an indicator of a set of CCA locations within the set ofconsecutive TTIs, a number of the set of CCA locations being common to aset of UEs that respectively utilize TTIs having different durations.The consecutive uplink transmission component 1550 may transmit, in theshared radio frequency spectrum band, an uplink transmission within aTTI of the set of consecutive TTIs based on a result of successful CCAperformed at one of the set of CCA locations.

The transmitter 1555 may transmit signals generated by other componentsof the device 1505. In some examples, the transmitter 1555 may becollocated with a receiver 1510 in a transceiver module. For example,the transmitter 1555 may be an example of aspects of the transceiver1720 described with reference to FIG. 17. The transmitter 1555 mayutilize a single antenna or a set of antennas.

FIG. 16 shows a block diagram 1600 of a communications manager 1605 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. The communications manager 1605may be an example of aspects of a communications manager 1415, acommunications manager 1515, or a communications manager 1710 describedherein. The communications manager 1605 may include a reserved resourcesindication receiver 1610, a CCA gap identifier 1615, a rate matchingcomponent 1620, a rate matched transmission component 1625, a powerlevel component 1630, a CCA component 1635, a reference signal collisioncomponent 1640, an uplink burst grant receiver 1645, a CCA locationscomponent 1650, and a consecutive uplink transmission component 1655.Each of these modules may communicate, directly or indirectly, with oneanother (e.g., via one or more buses).

The reserved resources indication receiver 1610 may receive an indicatorof reserved resources in a shared radio frequency spectrum band. In someexamples, the reserved resources indication receiver 1610 may receive abroadcast signaling including the indicator of the reserved resources,where the indicator of the reserved resources is specific to a cell thattransmitted the broadcast signaling. In some examples, the reservedresources indication receiver 1610 may receive a control signalingincluding the indicator of the reserved resources, where the indicatorof the reserved resources is specific to the UE. In some cases, thereserved resources include a set of random access resources. In somecases, the indicator is a bitmap that identifies a symbol level andresource block level rate matching resource set. In some cases, theindicator is a bitmap that identifies a symbol level and sub-resourceblock level rate matching resource set. In some cases, the rate matcheduplink shared data channel transmission is transmitted in an uplinkshared data channel and the indicator of the reserved resourcescomprises an implicit indication of the reserved resources based atleast in part on a configuration of a second uplink channel other thanthe uplink shared data channel.

The reserved resources indication receiver 1610 may receive an indicatorof a set of random access resources in a shared radio frequency spectrumband. In some cases, a random access occasion associated with a randomaccess resource of the set of random access resources includes one ormore of a random access cyclic prefix duration, a set of random accesssymbol periods, and a guard time.

The CCA gap identifier 1615 may identify a location of a CCA gaprelative to the reserved resources. The CCA gap identifier 1615 mayidentify a location of a CCA gap between a first random access resourceof the set of random access resources and a second random accessresource of the set of random access resources. The CCA gap identifier1615 perform a CCA procedure during the CCA gap. The CCA gap identifier1615 may determine whether to transmit on the second random accessresource based on a result of the CCA procedure. In some cases, theindicator indicates that the location of the CCA gap is between a firstrandom access resource of the set of random access resources and asecond random access resource of the set of random access resources.

In some examples, the CCA gap identifier 1615 may receive a grantindicating allocated resources within the shared radio frequencyspectrum band for the uplink shared data channel transmission, the grantindicating that the CCA gap occurs at a particular period of theallocated resources. In some other examples, the CCA gap identifier 1615may determine that the CCA gap is located between a first random accessresource of the set of random access resources and a second randomaccess resource of the set of random access resources. In some cases,the CCA gap identifier 1615 may identify the location of the CCA gapbetween each pair of random access resources within the set of randomaccess resources. In some cases, the CCA gap identifier 1615 mayindicate that the location of the CCA gap is between the first randomaccess resource and the second random access resource. In the cases, theCCA gap identifier 1615 may identify that the CCA may include aconfigurable number of symbol periods.

In some examples, the CCA gap identifier 1615 may determine that a firstsubset of the set of random access resources correspond to a first TTIand a second subset of the set of random access resources correspond toa second TTI. In some examples, the CCA gap identifier 1615 maydetermine whether to use the second subset of the set of random accessresources to transmit a random access message.

In some examples, the CCA gap identifier 1615 may determine to use thesecond subset of the set of random access resources to send the randomaccess message based on a TTI type indicator or a SFI associated withthe second TTI. In some examples, the CCA gap identifier 1615 mayreceive a configuration message that indicates whether to use a randomaccess resource of the set of random access resources that occurs withinthe second TTI.

The rate matching component 1620 may rate match an uplink shared datachannel transmission around the reserved resources and the CCA gap. Therate matched transmission component 1625 may transmit, within the sharedradio frequency spectrum band, the rate matched uplink shared datachannel transmission. In some cases, the rate matched uplink shared datachannel transmission is transmitted in an uplink shared data channel andthe indicator indicates a configuration of an uplink channel other thanthe uplink shared data channel.

The uplink burst grant receiver 1645 may receive an uplink burst grantallocating uplink resources in a shared radio frequency spectrum bandfor a set of consecutive TTIs.

The CCA locations component 1650 may receive an indicator of a set ofCCA locations within the set of consecutive TTIs, a number of the set ofCCA locations being common to a set of UEs that respectively utilizeTTIs having different durations. In some cases, the indicator indicatesto perform a CCA at each CCA location of the set of CCA location priorto transmission within a respective TTI of the set of TTIs correspondingto the each CCA location. In some other examples, the indicatorindicates to skip performing a CCA at a subsequent CCA location of theset of CCA locations based on determining that the shared radiofrequency spectrum band is available at a prior CCA location of the setof CCA locations.

The consecutive uplink transmission component 1655 may transmit, in theshared radio frequency spectrum band, an uplink transmission within aTTI of the set of consecutive TTIs based on a result of successful CCAperformed at one of the set of CCA locations. In some examples, theconsecutive uplink transmission component 1655 may continue transmissionfor the set of TTIs of the uplink burst grant without performing a CCAat subsequent CCA locations of the set of CCA locations based ondetermining that the shared radio frequency spectrum band is availableat a prior CCA location of the set of CCA locations.

The power level component 1630 may transmit the rate matched uplinkshared data channel transmission at a higher power level during a firstperiod that is shared with the reserved resources and at a lower powerlevel during a second period that is not shared with the reservedresources. In some examples, the power level component 1630 may transmituplink control information to indicate the higher power level for thefirst period.

In some examples, the power level component 1630 may identify the higherpower level for the first period based on one or more of downlinkcontrol information, a power level for the second period, a bandwidth ofthe reserved resources, a bandwidth of a shared data channel, modulationof the shared data channel, a transmit power spectral densityregulation, or any combination thereof.

The CCA component 1635 may perform a CCA prior to resuming transmissionof the rate matched uplink shared data channel transmission, infrequencies occupied by the reserved resources, after an end of thereserved resources and the CCA gap.

The reference signal collision component 1640 may determine that areference signal is scheduled for transmission within the reservedresources or the CCA gap. In some examples, the reference signalcollision component 1640 may determine not to transmit the referencesignal. In some examples, the reference signal collision component 1640may transmit the reference signal in resources that are not within thereserved resources or the CCA gap. In some examples, the referencesignal collision component 1640 may transmit the reference signal asscheduled.

In some examples, the reference signal collision component 1640 may skiptransmitting of the rate matched uplink shared data channel transmissionin a scheduled TTI, where transmitting the rate matched uplink shareddata channel transmission occurs in a different TTI than the scheduledTTI. In some examples, the reference signal collision component 1640 maytransmit the reference signal using a first reference signal pattern ofa set of reference signal patterns, where the first reference signalpattern identifies resources that do not overlap with the reservedresources or the CCA gap. In some cases, the first reference signalpattern indicates a shift of at least one symbol of the reference signalto avoid a collision between the reference signal and the reservedresources, the CCA gap, or both.

In some examples, the reference signal collision component 1640 mayselect a collision response from a set of different collisions responsesbased on determining that a reference signal is scheduled fortransmission within the reserved resources or the CCA gap.

In some examples, the reference signal collision component 1640 mayselect the collision response from the set of different collisionresponses based on a number of symbols of the reference signal, a numberof symbols of the reference signal that collide with the reservedresources or the CCA gap, a waveform type of the uplink shared datachannel transmission, DCI signaling, whether the reference signal isscheduled for transmission within the reserved resources, whetherreference signal is scheduled for transmission within the CCA gap, atype of the reserved resources, or any combination thereof.

In some examples, the reference signal collision component 1640 maydetermine that the reference signal is scheduled to be transmittedduring a set of symbols. In some examples, the reference signalcollision component 1640 may apply the selected collision response toadjust in which symbol the reference signal is transmitted on up to eachsymbol of the set of symbols. In some examples, the reference signalcollision component 1640 may determine that a reference signal isscheduled for transmission within the reserved resources, the reservedresources using a tone interlace structure. In some examples, thereference signal collision component 1640 may transmit the referencesignal in an unreserved tone level interlace of the tone interlacestructure.

FIG. 17 shows a diagram of a system 1700 including a device 1705 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. The device 1705 may be anexample of or include the components of device 1405, device 1505, or aUE 115 as described herein. The device 1705 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a communicationsmanager 1710, an I/O controller 1715, a transceiver 1720, an antenna1725, memory 1730, and a processor 1740. These components may be inelectronic communication via one or more buses (e.g., bus 1745).

The communications manager 1710 may receive an indicator of reservedresources in a shared radio frequency spectrum band, rate match anuplink shared data channel transmission around the reserved resources,and transmit, within the shared radio frequency spectrum band, the ratematched uplink shared data channel transmission. In some cases, thecommunications manager 1710 may identify a location of a CCA gaprelative to the reserved resources. In some cases, the communicationsmanager 1710 may rate match the uplink shared data channel transmissionaround the CCA gap.

The communications manager 1710 may also receive an uplink burst grantallocating uplink resources in a shared radio frequency spectrum bandfor a set of consecutive TTIs, receive an indicator of a set of CCAlocations within the set of consecutive TTIs, a number of the set of CCAlocations being common to a set of UEs that respectively utilize TTIshaving different durations, and transmit, in the shared radio frequencyspectrum band, an uplink transmission within a TTI of the set ofconsecutive TTIs based on a result of successful CCA performed at one ofthe set of CCA locations.

The communications manager 1710 may also receive an indicator of a setof random access resources in a shared radio frequency spectrum band,identifying a location of a CCA gap between a first random accessresource of the set of random access resources and a second randomaccess resource of the set of random access resources, perform a CCAprocedure during the CCA gap, and determine whether to transmit on thesecond random access resource based at least a result of the CCAprocedure.

The I/O controller 1715 may manage input and output signals for thedevice 1705. The I/O controller 1715 may also manage peripherals notintegrated into the device 1705. In some cases, the I/O controller 1715may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1715 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1715may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1715may be implemented as part of a processor. In some cases, a user mayinteract with the device 1705 via the I/O controller 1715 or viahardware components controlled by the I/O controller 1715.

The transceiver 1720 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1720 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1720 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1725.However, in some cases the device may have more than one antenna 1725,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1730 may include RAM and ROM. The memory 1730 may storecomputer-readable, computer-executable code 1735 including instructionsthat, when executed, cause the processor to perform various functionsdescribed herein. In some cases, the memory 1730 may contain, amongother things, a BIOS which may control basic hardware or softwareoperation such as the interaction with peripheral components or devices.

The processor 1740 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1740 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1740. The processor 1740 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1730) to cause the device 1705 to perform variousfunctions (e.g., functions or tasks supporting shared channel designaround reserved resources).

The code 1735 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1735 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1735 may not be directly executable by theprocessor 1740 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 18 shows a block diagram 1800 of a device 1805 that supports sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure. The device 1805 may be an example of aspects ofa base station 105 as described herein. The device 1805 may include areceiver 1810, a communications manager 1815, and a transmitter 1820.The device 1805 may also include a processor. Each of these componentsmay be in communication with one another (e.g., via one or more buses).

The receiver 1810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to sharedchannel design around reserved resources, etc.). Information may bepassed on to other components of the device 1805. The receiver 1810 maybe an example of aspects of the transceiver 2120 described withreference to FIG. 21. The receiver 1810 may utilize a single antenna ora set of antennas.

The communications manager 1815 may transmit an indicator of reservedresources in a shared radio frequency spectrum band, receive, within theshared radio frequency spectrum band, a rate matched uplink shared datachannel transmission, and de-rate match the rate matched uplink shareddata channel transmission based on the reserved resources. In somecases, the communications manager 1815 may identify a location of a CCAgap relative to the reserved resources. In some cases, thecommunications manager 1815 may de-rate match the rate matched uplinkshared data channel transmission based on the location of the CCA gap.

The communications manager 1815 may also transmit an uplink burst grantallocating uplink resources in a shared radio frequency spectrum bandfor a set of consecutive TTIs, transmit an indicator of a set of CCAlocations within the set of consecutive TTIs, a number of the set of CCAlocations being common to a set of UEs that respectively utilize TTIshaving different durations, and receive, in the shared radio frequencyspectrum band, an uplink transmission within a first TTI of the set ofconsecutive TTIs. The communications manager 1815 may be an example ofaspects of the communications manager 2110 described herein.

The communications manager 1815 may transmit an indicator of a set ofrandom access resources in a shared radio frequency spectrum band,identify a location of a CCA gap between a first random access resourceof the set of random access resources and a second random accessresource of the set of random access resources, and monitor the secondrandom access resource based on the location of the CCA gap.

The communications manager 1815, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1815, or itssub-components may be executed by a general-purpose processor, a DSP, anASIC, a FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The communications manager 1815, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1815, or its sub-components, may be a separateand distinct component in accordance with various aspects of the presentdisclosure. In some examples, the communications manager 1815, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.

The transmitter 1820 may transmit signals generated by other componentsof the device 1805. In some examples, the transmitter 1820 may becollocated with a receiver 1810 in a transceiver module. For example,the transmitter 1820 may be an example of aspects of the transceiver2120 described with reference to FIG. 21. The transmitter 1820 mayutilize a single antenna or a set of antennas.

FIG. 19 shows a block diagram 1900 of a device 1905 that supports sharedchannel design around reserved resources in accordance with aspects ofthe present disclosure. The device 1905 may be an example of aspects ofa device 1805 or a base station 105 as described herein. The device 1905may include a receiver 1910, a communications manager 1915, and atransmitter 1955. The device 1905 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 1910 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to sharedchannel design around reserved resources, etc.). Information may bepassed on to other components of the device 1905. The receiver 1910 maybe an example of aspects of the transceiver 2120 described withreference to FIG. 21. The receiver 1910 may utilize a single antenna ora set of antennas.

The communications manager 1915 may be an example of aspects of thecommunications manager 1815 as described herein. The communicationsmanager 1915 may include a reserved resources indication transmitter1920, a CCA gap identifier 1925, a rate match uplink transmissionreceiver 1930, a de-rate matching component 1935, an uplink burst granttransmitter 1940, a CCA locations indicator 1945, and a burst uplinktransmission receiver 1950. The communications manager 1915 may be anexample of aspects of the communications manager 2110 described herein.The reserved resources indication transmitter 1920 may transmit anindicator of reserved resources in a shared radio frequency spectrumband. The CCA gap identifier 1925 may identify a location of a CCA gaprelative to the reserved resources. The rate match uplink transmissionreceiver 1930 may receive, within the shared radio frequency spectrumband, a rate matched uplink shared data channel transmission. Thede-rate matching component 1935 may de-rate match the rate matcheduplink shared data channel transmission based on the reserved resources.In some cases, the de-rate matching component 1935 may de-rate match therate matched uplink shared data channel transmission based on thelocation of the CCA gap

The reserved resources indication transmitter 1920 may transmit anindicator of a set of random access resources in a shared radiofrequency spectrum band. The CCA gap identifier 1925 may identify alocation of a CCA gap between a first random access resource of the setof random access resources and a second random access resource of theset of random access resources. The CCA gap identifier 1925 may monitorthe second random access resource based on the location of the CCA gap.The uplink burst grant transmitter 1940 may transmit an uplink burstgrant allocating uplink resources in a shared radio frequency spectrumband for a set of consecutive TTIs. The CCA locations indicator 1945 maytransmit an indicator of a set of CCA locations within the set ofconsecutive TTIs, a number of the set of CCA locations being common to aset of UEs that respectively utilize TTIs having different durations.The burst uplink transmission receiver 1950 may receive, in the sharedradio frequency spectrum band, an uplink transmission within a first TTIof the set of consecutive TTIs.

The transmitter 1955 may transmit signals generated by other componentsof the device 1905. In some examples, the transmitter 1955 may becollocated with a receiver 1910 in a transceiver module. For example,the transmitter 1955 may be an example of aspects of the transceiver2120 described with reference to FIG. 21. The transmitter 1955 mayutilize a single antenna or a set of antennas.

FIG. 20 shows a block diagram 2000 of a communications manager 2005 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. The communications manager 2005may be an example of aspects of a communications manager 1815, acommunications manager 1915, or a communications manager 2110 describedherein. The communications manager 2005 may include a reserved resourcesindication transmitter 2010, a CCA gap identifier 2015, a rate matchuplink transmission receiver 2020, a de-rate matching component 2025, areference signal collision component 2030, a reference signal patterncomponent 2035, an uplink burst grant transmitter 2040, a CCA locationsindicator 2045, and a burst uplink transmission receiver 2050. Each ofthese modules may communicate, directly or indirectly, with one another(e.g., via one or more buses).

The reserved resources indication transmitter 2010 may transmit anindicator of reserved resources in a shared radio frequency spectrumband. In some examples, the reserved resources indication transmitter2010 may receive a random access message during a first random accessresource of the set of random access resources. In some examples, thereserved resources indication transmitter 2010 may receive a randomaccess message during each random access resource of the set of randomaccess resources.

In some cases, the reserved resources include a set of random accessresources. In some cases, the indicator indicates that the location ofthe CCA gap is between a first random access resource of the set ofrandom access resources and a second random access resource of the setof random access resources. In some cases, the indicator is a bitmapthat identifies a symbol level and resource block level rate matchingresource set or identifies a symbol level and sub-resource block levelrate matching resource set.

The CCA gap identifier 2015 may identify a location of a CCA gaprelative to the reserved resources. In some examples, the CCA gapidentifier 2015 may transmit a grant indicating the location of the CCAgap. The CCA gap identifier 2015, may identify a CCA gap that includes aconfigurable number of symbol periods.

The rate match uplink transmission receiver 2020 may receive, within theshared radio frequency spectrum band, a rate matched uplink shared datachannel transmission.

The de-rate matching component 2025 may de-rate match the rate matcheduplink shared data channel transmission based on the reserved resources.In some cases, the de-rate matching component 2025 may de-rate match therate matched uplink shared data channel transmission based on thelocation of the CCA gap.

The reference signal collision component 2030 may transmit DCIindicating a collision response for a reference signal colliding withthe reserved resources. In some examples, the reference signal collisioncomponent 2030 may identify a reference signal pattern based on thecollision response. In some examples, the reference signal collisioncomponent 2030 may demodulate the rate matched uplink shared datachannel transmission based on the reference signal pattern.

The reference signal pattern component 2035 may receive uplink controlinformation (UCI) indicating a reference signal pattern. In someexamples, the reference signal pattern component 2035 may demodulate therate matched uplink shared data channel transmission based on thereference signal pattern.

The uplink burst grant transmitter 2040 may transmit an uplink burstgrant allocating uplink resources in a shared radio frequency spectrumband for a set of consecutive TTIs.

The CCA locations indicator 2045 may transmit an indicator of a set ofCCA locations within the set of consecutive TTIs, a number of the set ofCCA locations being common to a set of UEs that respectively utilizeTTIs having different durations. In some cases, the indicator indicatesto perform a CCA at each CCA location of the set of CCA locations priorto transmission within a respective TTI of the set of TTIs correspondingto the each CCA location. In some cases, the indicator indicates to skipperforming a CCA at a subsequent CCA location of the set of CCAlocations based on determining that the shared radio frequency spectrumband is available at a prior CCA location of the set of CCA locations.

The burst uplink transmission receiver 2050 may receive, in the sharedradio frequency spectrum band, an uplink transmission within a first TTIof the set of consecutive TTIs.

FIG. 21 shows a diagram of a system 2100 including a device 2105 thatsupports shared channel design around reserved resources in accordancewith aspects of the present disclosure. The device 2105 may be anexample of or include the components of device 1805, device 1905, or abase station 105 as described herein. The device 2105 may includecomponents for bi-directional voice and data communications includingcomponents for transmitting and receiving communications, including acommunications manager 2110, a network communications manager 2115, atransceiver 2120, an antenna 2125, memory 2130, a processor 2140, and aninter-station communications manager 2145. These components may be inelectronic communication via one or more buses (e.g., bus 2150).

The communications manager 2110 may transmit an indicator of reservedresources in a shared radio frequency spectrum band, receive, within theshared radio frequency spectrum band, a rate matched uplink shared datachannel transmission, and de-rate match the rate matched uplink shareddata channel transmission based on the reserved resources. In somecases, the communications manager 2110 may identify a location of a CCAgap relative to the reserved resources. In some cases, thecommunications manager 2110 may de-rate match the rate matched uplinkshared data channel transmission based on the location of the CCA gap.

The communications manager 2110 may also transmit an uplink burst grantallocating uplink resources in a shared radio frequency spectrum bandfor a set of consecutive TTIs, transmit an indicator of a set of CCAlocations within the set of consecutive TTIs, a number of the set of CCAlocations being common to a set of UEs that respectively utilize TTIshaving different durations, and receive, in the shared radio frequencyspectrum band, an uplink transmission within a first TTI of the set ofconsecutive TTIs.

The network communications manager 2115 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 2115 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 2120 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 2120 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 2120 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 2125.However, in some cases the device may have more than one antenna 2125,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 2130 may include RAM, ROM, or a combination thereof. Thememory 2130 may store computer-readable code 2135 including instructionsthat, when executed by a processor (e.g., the processor 2140) cause thedevice to perform various functions described herein. In some cases, thememory 2130 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 2140 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 2140 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 2140. The processor 2140 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 2130) to cause the device 2105 to perform various functions(e.g., functions or tasks supporting shared channel design aroundreserved resources).

The inter-station communications manager 2145 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager2145 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager2145 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 2135 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 2135 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 2135 may not be directly executable by theprocessor 2140 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 22 shows a flowchart illustrating a method 2200 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. The operations of method 2200 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 2200 may be performed by acommunications manager as described with reference to FIGS. 14 through17. In some examples, a UE may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedherein. Additionally or alternatively, a UE may perform aspects of thefunctions described herein using special-purpose hardware.

At 2205, the UE may receive an indicator of reserved resources in ashared radio frequency spectrum band. The operations of 2205 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2205 may be performed by a reservedresources indication receiver as described with reference to FIGS. 14through 17.

In some implementations, the UE may identify a location of a CCA gaprelative to the reserved resources. Identifying the location of the CCAgap relative to the reserved resources may be performed according to themethods described herein. In some examples, aspects identifying thelocation of the CCA gap relative to the reserved resources may beperformed by a CCA gap identifier as described with reference to FIGS.14 through 17.

At 2210, the UE may rate match an uplink shared data channeltransmission around the reserved resources. The operations of 2210 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 2210 may be performed by a ratematching component as described with reference to FIGS. 14 through 17.

At 2215, the UE may transmit, within the shared radio frequency spectrumband, the rate matched uplink shared data channel transmission. Theoperations of 2215 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2215 may beperformed by a rate matched transmission component as described withreference to FIGS. 14 through 17.

FIG. 23 shows a flowchart illustrating a method 2300 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. The operations of method 2300 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 2300 may be performed by acommunications manager as described with reference to FIGS. 14 through17. In some examples, a UE may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedherein. Additionally or alternatively, a UE may perform aspects of thefunctions described herein using special-purpose hardware.

At 2305, the UE may receive an indicator of reserved resources in ashared radio frequency spectrum band. The operations of 2305 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2305 may be performed by a reservedresources indication receiver as described with reference to FIGS. 14through 17.

At 2310, the UE may identify a location of a CCA gap relative to thereserved resources. The operations of 2310 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 2310 may be performed by a CCA gap identifier as describedwith reference to FIGS. 14 through 17.

At 2315, the UE may determine that a reference signal is scheduled fortransmission within the reserved resources or the CCA gap. Theoperations of 2315 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2315 may beperformed by a reference signal collision component as described withreference to FIGS. 14 through 17.

At 2320, the UE may rate match an uplink shared data channeltransmission around the reserved resources and the CCA gap. Theoperations of 2320 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2320 may beperformed by a rate matching component as described with reference toFIGS. 14 through 17.

At 2325, the UE may transmit, within the shared radio frequency spectrumband, the rate matched uplink shared data channel transmission. Theoperations of 2325 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2325 may beperformed by a rate matched transmission component as described withreference to FIGS. 14 through 17.

At 2330, the UE may transmit the reference signal in resources that arenot within the reserved resources or the CCA gap. The operations of 2330may be performed according to the methods described herein. In someexamples, aspects of the operations of 2330 may be performed by areference signal collision component as described with reference toFIGS. 14 through 17.

FIG. 24 shows a flowchart illustrating a method 2400 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. The operations of method 2400 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 2400 may be performed by acommunications manager as described with reference to FIGS. 18 through21. In some examples, a base station may execute a set of instructionsto control the functional elements of the base station to perform thefunctions described herein. Additionally or alternatively, a basestation may perform aspects of the functions described herein usingspecial-purpose hardware.

At 2405, the base station may transmit an indicator of reservedresources in a shared radio frequency spectrum band. The operations of2405 may be performed according to the methods described herein. In someexamples, aspects of the operations of 2405 may be performed by areserved resources indication transmitter as described with reference toFIGS. 18 through 21.

In some implementations, the base station may identify a location of aCCA gap relative to the reserved resources. Identifying the location ofthe CCA gap relative to the reserved resources may be performedaccording to the methods described herein. In some examples, aspects ofidentifying the location of the CCA gap relative to the reservedresources may be performed by a CCA gap identifier as described withreference to FIGS. 18 through 21.

At 2410, the base station may receive, within the shared radio frequencyspectrum band, a rate matched uplink shared data channel transmission.The operations of 2410 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2410may be performed by a rate match uplink transmission receiver asdescribed with reference to FIGS. 18 through 21.

At 2415, the base station may de-rate match the rate matched uplinkshared data channel transmission based on the reserved resources. Theoperations of 2415 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2415 may beperformed by a de-rate matching component as described with reference toFIGS. 18 through 21.

FIG. 25 shows a flowchart illustrating a method 2500 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. The operations of method 2500 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 2500 may be performed by acommunications manager as described with reference to FIGS. 14 through17. In some examples, a UE may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedherein. Additionally or alternatively, a UE may perform aspects of thefunctions described herein using special-purpose hardware.

At 2505, the UE may receive an uplink burst grant allocating uplinkresources in a shared radio frequency spectrum band for a set ofconsecutive TTIs. The operations of 2505 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 2505 may be performed by an uplink burst grant receiver asdescribed with reference to FIGS. 14 through 17.

At 2510, the UE may receive an indicator of a set of CCA locationswithin the set of consecutive TTIs, a number of the set of CCA locationsbeing common to a set of UEs that respectively utilize TTIs havingdifferent durations. The operations of 2510 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 2510 may be performed by a CCA locations component asdescribed with reference to FIGS. 14 through 17.

At 2515, the UE may transmit, in the shared radio frequency spectrumband, an uplink transmission within a TTI of the set of consecutive TTIsbased on a result of successful CCA performed at one of the set of CCAlocations. The operations of 2515 may be performed according to themethods described herein. In some examples, aspects of the operations of2515 may be performed by a consecutive uplink transmission component asdescribed with reference to FIGS. 14 through 17.

In some cases, at 2520, the UE may transmit, in the shared radiofrequency spectrum band, an uplink transmission within each TTI of theset of consecutive TTIs that occur after the first TTI, with or withoutperforming CCA at each subsequent CCA location of the set of CCAlocations. The operations of 2520 may optionally be performed accordingto the methods described herein. In some examples, aspects of theoperations of 2520 may be performed by a consecutive uplink transmissioncomponent as described with reference to FIGS. 14 through 17.

FIG. 26 shows a flowchart illustrating a method 2600 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. The operations of method 2600 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 2600 may be performed by acommunications manager as described with reference to FIGS. 18 through21. In some examples, a base station may execute a set of instructionsto control the functional elements of the base station to perform thefunctions described herein. Additionally or alternatively, a basestation may perform aspects of the functions described herein usingspecial-purpose hardware.

At 2605, the base station may transmit an uplink burst grant allocatinguplink resources in a shared radio frequency spectrum band for a set ofconsecutive TTIs. The operations of 2605 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 2605 may be performed by an uplink burst grant transmitteras described with reference to FIGS. 18 through 21.

At 2610, the base station may transmit an indicator of a set of CCAlocations within the set of consecutive TTIs, a number of the set of CCAlocations being common to a set of UEs that respectively utilize TTIshaving different durations. The operations of 2610 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2610 may be performed by a CCA locations indicator asdescribed with reference to FIGS. 18 through 21.

At 2615, the base station may receive, in the shared radio frequencyspectrum band, an uplink transmission within a first TTI of the set ofconsecutive TTIs. The operations of 2615 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 2615 may be performed by a burst uplink transmissionreceiver as described with reference to FIGS. 18 through 21.

FIG. 27 shows a flowchart illustrating a method 2700 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. The operations of method 2700 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 2700 may be performed by acommunications manager as described with reference to FIGS. 14 through17. In some examples, a UE may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedherein. Additionally or alternatively, a UE may perform aspects of thefunctions described herein using special-purpose hardware.

At 2705, receive an indicator of a set of random access resources in ashared radio frequency spectrum band. The operations of 2705 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2705 may be performed by a reservedresources indication receiver as described with reference to FIGS. 14through 17.

At 2710, the UE may identify a location of a CCA gap between a firstrandom access resource of the set of random access resources and asecond random access resource of the set of random access resources. Theoperations of 2710 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2710 may beperformed by a CCA gap identifier as described with reference to FIGS.14 through 17.

At 2715, the UE may perform a CCA procedure during the CCA gap. Theoperations of 2715 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2715 may beperformed by a CCA gap identifier as described with reference to FIGS.14 through 17.

At 2720, the UE may determine whether to transmit on the second randomaccess resource based on a result of the CCA procedure. The operationsof 2720 may be performed according to the methods described herein. Insome examples, aspects of the operations of 2720 may be performed by arate matched transmission component as described with reference to FIGS.14 through 17.

FIG. 28 shows a flowchart illustrating a method 2800 that supportsshared channel design around reserved resources in accordance withaspects of the present disclosure. The operations of method 2800 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 2800 may be performed by acommunications manager as described with reference to FIGS. 18 through21. In some examples, a base station may execute a set of instructionsto control the functional elements of the base station to perform thefunctions described herein. Additionally or alternatively, a basestation may perform aspects of the functions described herein usingspecial-purpose hardware.

At 2805, the base station may transmit an indicator of a set of randomaccess resources in a shared radio frequency spectrum band. Theoperations of 2805 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2805 may beperformed by a reserved resources indication transmitter as describedwith reference to FIGS. 18 through 21.

At 2810, the base station may identify a location of a CCA gap between afirst random access resource of the set of random access resources and asecond random access resource of the set of random access resources. Theoperations of 2810 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2810 may beperformed by a CCA gap identifier as described with reference to FIGS.18 through 21.

At 2815, the base station may monitor the second random access resourcebased on the location of the CCA gap. The operations of 2815 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2815 may be performed by CCA gap identifieras described with reference to FIGS. 18 through 21.

In some cases, the techniques described herein may lead to someadvantages for a UE 115 and base station 105. For example, by ratematching an uplink shared data channel transmission around reservedresources, throughput may on uplink shared channels be increased. Thesetechniques may support the UE 115 to meet stringent reliability andlatency conditions for some types of communications (e.g., URLLC) whilestill providing high throughput for other types of communications.Moreover, internal components of the UE 115 applying the techniques mayimprove power utilization by improving spectral efficiency such that theUE 115 performs fewer CCA procedures, which may reduce power consumptionfor components in the UE 115. Additionally, the techniques of providingCCA gaps between (e.g., and before) RACH occasions may increase spectralefficiency, throughput, and latency considerations, as the UE 115 mayhave increased likelihood to gain control of the transmission medium.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned above as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEs115 with service subscriptions with the network provider. A small cellmay be associated with a lower-powered base station 105, as comparedwith a macro cell, and a small cell may operate in the same or different(e.g., licensed, unlicensed, etc.) frequency bands as macro cells. Smallcells may include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs 115 with servicesubscriptions with the network provider. A femto cell may also cover asmall geographic area (e.g., a home) and may provide restricted accessby UEs 115 having an association with the femto cell (e.g., UEs 115 in aclosed subscriber group (CSG), UEs 115 for users in the home, and thelike). An eNB for a macro cell may be referred to as a macro eNB. An eNBfor a small cell may be referred to as a small cell eNB, a pico eNB, afemto eNB, or a home eNB. An eNB may support one or multiple (e.g., two,three, four, and the like) cells, and may also support communicationsusing one or multiple component carriers.

The wireless communications system 100 or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations 105 may have similar frame timing, andtransmissions from different base stations 105 may be approximatelyaligned in time. For asynchronous operation, the base stations 105 mayhave different frame timing, and transmissions from different basestations 105 may not be aligned in time. The techniques described hereinmay be used for either synchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), an ASIC, aFPGA or other programmable logic device (PLD), discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described herein. Ageneral-purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude random-access memory (RAM), read-only memory (ROM), electricallyerasable programmable read only memory (EEPROM), flash memory, compactdisk (CD) ROM or other optical disk storage, magnetic disk storage orother magnetic storage devices, or any other non-transitory medium thatcan be used to carry or store desired program code means in the form ofinstructions or data structures and that can be accessed by ageneral-purpose or special-purpose computer, or a general-purpose orspecial-purpose processor. Also, any connection is properly termed acomputer-readable medium. For example, if the software is transmittedfrom a website, server, or other remote source using a coaxial cable,fiber optic cable, twisted pair, digital subscriber line (DSL), orwireless technologies such as infrared, radio, and microwave, then thecoaxial cable, fiber optic cable, twisted pair, DSL, or wirelesstechnologies such as infrared, radio, and microwave are included in thedefinition of medium. Disk and disc, as used herein, include CD, laserdisc, optical disc, digital versatile disc (DVD), floppy disk andBlu-ray disc where disks usually reproduce data magnetically, whilediscs reproduce data optically with lasers. Combinations of the aboveare also included within the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communication at a userequipment (UE), comprising: receiving an indicator of a plurality ofrandom access resources in a shared radio frequency spectrum band;identifying a location of a clear channel assessment (CCA) gap between afirst random access resource of the plurality of random access resourcesand a second random access resource of the plurality of random accessresources; performing a CCA procedure during the CCA gap; anddetermining whether to transmit on the second random access resourcebased at least in part on a result of the CCA procedure.
 2. The methodof claim 1, wherein the indicator indicates that the location of the CCAgap is between the first random access resource and the second randomaccess resource.
 3. The method of claim 1, wherein the CCA gap comprisesa configurable number of symbol periods.
 4. The method of claim 1,wherein a random access occasion associated with a random accessresource of the plurality of random access resources comprises one ormore of a random access cyclic prefix duration, a set of random accesssymbol periods, and a guard time.
 5. The method of claim 1, whereinidentifying the location of the CCA gap further comprises: determiningthat the CCA gap is located between the first random access resource andthe second random access resource.
 6. The method of claim 1, whereinidentifying the location of the CCA gap further comprises: identifyingthe location of the CCA gap between each pair of random access resourceswithin the plurality of random access resources.
 7. The method of claim6, further comprising: determining that a first subset of the pluralityof random access resources correspond to a first TTI and a second subsetof the plurality of random access resources correspond to a second TTI;and determining whether to use the second subset of the plurality ofrandom access resources to transmit a random access message.
 8. Themethod of claim 7, wherein determining whether to use the second subsetof the plurality of random access resources further comprises:determining to use the second subset of the plurality of random accessresources to send the random access message based at least in part on aTTI type indicator or a subframe format indicator (SFI) associated withthe second TTI.
 9. The method of claim 7, wherein determining whether touse the second subset of the plurality of random access resourcesfurther comprises: receiving a configuration message that indicateswhether to use a random access resource of the plurality of randomaccess resources that occurs within the second TTI.
 10. A method forwireless communication at a base station, comprising: transmitting anindicator of a plurality of random access resources in a shared radiofrequency spectrum band; identifying a location of a clear channelassessment (CCA) gap between a first random access resource of theplurality of random access resources and a second random access resourceof the plurality of random access resources; and monitoring the secondrandom access resource based at least in part on the location of the CCAgap.
 11. The method of claim 10, wherein the indicator indicates thatthe location of the CCA gap is between the first random access resourceof the plurality of random access resources and the second random accessresource of the plurality of random access resources.
 12. The method ofclaim 10, wherein the CCA gap comprises a configurable number of symbolperiods.
 13. The method of claim 10, further comprising: receiving arandom access message during the first random access resource of theplurality of random access resources.
 14. The method of claim 10,further comprising: receiving a random access message during each randomaccess resource of the plurality of random access resources.
 15. Anapparatus for wireless communication at a user equipment (UE),comprising: a processor; memory coupled with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to: receive an indicator of a plurality of randomaccess resources in a shared radio frequency spectrum band; identify alocation of a clear channel assessment (CCA) gap between a first randomaccess resource of the plurality of random access resources and a secondrandom access resource of the plurality of random access resources;perform a CCA procedure during the CCA gap; and determine whether totransmit on the second random access resource based at least in part ona result of the CCA procedure.
 16. The apparatus of claim 15, whereinthe indicator indicates that the location of the CCA gap is between thefirst random access resource and the second random access resource. 17.The apparatus of claim 15, wherein the CCA gap comprises a configurablenumber of symbol periods.
 18. The apparatus of claim 15, wherein arandom access occasion associated with a random access resource of theplurality of random access resources comprises one or more of a randomaccess cyclic prefix duration, a set of random access symbol periods,and a guard time.
 19. The apparatus of claim 15, wherein theinstructions to identify the location of the CCA gap are furtherexecutable by the processor to cause the apparatus to: determine thatthe CCA gap is located between the first random access resource and thesecond random access resource.
 20. The apparatus of claim 15, whereinthe instructions to identify the location of the CCA gap are furtherexecutable by the processor to cause the apparatus to: identify thelocation of the CCA gap between each pair of random access resourceswithin the plurality of random access resources.
 21. The apparatus ofclaim 20, wherein the instructions are further executable by theprocessor to cause the apparatus to: determine that a first subset ofthe plurality of random access resources correspond to a first TTI and asecond subset of the plurality of random access resources correspond toa second TTI; and determine whether to use the second subset of theplurality of random access resources to transmit a random accessmessage.
 22. The apparatus of claim 21, wherein the instructions todetermine whether to use the second subset of the plurality of randomaccess resources are further executable by the processor to cause theapparatus to: determine to use the second subset of the plurality ofrandom access resources to send the random access message based at leastin part on a TTI type indicator or a subframe format indicator (SFI)associated with the second TTI.
 23. The apparatus of claim 21, whereinthe instructions to determine whether to use the second subset of theplurality of random access resources are further executable by theprocessor to cause the apparatus to: receive a configuration messagethat indicates whether to use a random access resource of the pluralityof random access resources that occurs within the second TTI.
 24. Anapparatus for wireless communication at a base station, comprising: aprocessor; memory coupled with the processor; and instructions stored inthe memory and executable by the processor to cause the apparatus to:transmit an indicator of a plurality of random access resources in ashared radio frequency spectrum band; identify a location of a clearchannel assessment (CCA) gap between a first random access resource ofthe plurality of random access resources and a second random accessresource of the plurality of random access resources; and monitor thesecond random access resource based at least in part on the location ofthe CCA gap.
 25. The apparatus of claim 24, wherein the indicatorindicates that the location of the CCA gap is between the first randomaccess resource of the plurality of random access resources and thesecond random access resource of the plurality of random accessresources.
 26. The apparatus of claim 24, wherein the CCA gap comprisesa configurable number of symbol periods.
 27. The apparatus of claim 24,wherein the instructions are further executable by the processor tocause the apparatus to: receive a random access message during the firstrandom access resource of the plurality of random access resources. 28.The apparatus of claim 24, wherein the instructions are furtherexecutable by the processor to cause the apparatus to: receive a randomaccess message during each random access resource of the plurality ofrandom access resources.